# My PC keeps turning on and off every 3 seconds. Is my motherboard faulty?



## Frostified (Nov 17, 2019)

Hey, so the other day my PC suddenly shut down and there was a burning smell and I couldn't turn it on. The PSU was working just fine when I shorted it to test it. I tried booting my PC without the GPU and it turns on for 2 to 3 seconds then turns off. There is no beep to indicate a boot.

I tried placing my GPU in another PC and booting and there was a loud noise followed by a blown fuse on the PSU plug (the wall plug) so I am pretty sure my GPU fried. The question is if it affected the motherboard too. I thoroughly checked over it and there doesn't seem to be any broken sokders or blown parts.

Finally, one of my fans that is connected in the bottom part of my motherboard, near where the Front Panel is, spins A LOT slower than the other fan which is plugged near the top part of the motherboard. When I switch their plugs, the one in the bottom plug always spins slower.

My question is, do you think the problem is in my motherboard for the constant turning on and off?

Things I have tried:
- Taking out the motherboard battery.
- Changing RAM slots.

SPECS:
CPU - Intel i7 6700k
Motherboard - Gigabyte GA-z170-Gaming K3
GPU - GTX 9i80 Ti G1 Gaming
PSU - Corsair CX 750W


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## Zach_01 (Nov 18, 2019)

You have to give more info... Detailed all system specs (PSU, CPU, MAINBOARD, GPU) and what you were doing when that happend. Any overclocking(CPU,GPU)? Cooling solutions(CPU,GPU,PSU,case)?. Have you ever monitor any temperatures of the system and its components?

There is no real way for any of us to know what parts affected by this burn...
You must install another (cheap)GPU and see the condition rest of them.
But don’t do anything until you give us the details first of your system.


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## Khonjel (Nov 18, 2019)

Have to test everything one by one. But most probably original culprit was the power supply. I have to thank my last power supply that at least it didn't kill anything else when it went out.


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## Mac2580 (Nov 18, 2019)

Yes my best guess would be that its a Power Supply issue. Without testing the board and GPU seperately, its just a guess.


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## AsRock (Nov 18, 2019)

All so thinking it's the PSU, any chance you hav a spare or a friend with one you can borrow ?.

PSU might be failing when there is a load put on it.


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## btarunr (Nov 18, 2019)

This happened to me. It was a faulty PSU in my case.


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## Frostified (Nov 18, 2019)

Zach_01 said:


> You have to give more info... Detailed all system specs (PSU, CPU, MAINBOARD, GPU) and what you were doing when that happend. Any overclocking(CPU,GPU)? Cooling solutions(CPU,GPU,PSU,case)?. Have you ever monitor any temperatures of the system and its components?
> 
> There is no real way for any of us to know what parts affected by this burn...
> You must install another (cheap)GPU and see the condition rest of them.
> But don’t do anything until you give us the details first of your system.



Right, my bad. Here's a list of my specs.

CPU - Intel i7 6700k
Motherboard - Gigabyte GA-z170-Gaming K3
GPU - GTX 9i80 Ti G1 Gaming
PSU - Corsair CX 750W

I have never overclocked anything. The case I was using had terrible airflow and my GPU was constantly at 80°C if I was playing something intensive or my room was warmer than usual. At the time of the burn, I was playing a very light performance game (World of Warcraft) but my room was around 26/27°C and my GPU somewhere near 80°C as well.

I only tested if the PSU is working with a short. I suppose it can still be faulty without me know. The PSU I used to test if my GPU in another PC was 500W when the minimum for my GPU is 600W. Maybe that is why the fuse on the plug broke so it's not an indicator if my GPU fried.


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## Zach_01 (Nov 18, 2019)

First thought, before you write the specs, was also the PSU like all others responded... But now seeing the them I suspect that the GPU has gone. The CX line PSUs from Corsair is not the best but I cant imagine a 750W PSU not handling a 400~450W PC.

The 980Ti is a high power draw (~250W) gpu and has a reccomended minimum of 600W PSU but this is only for gaming. A 500W PSU for sure can at least initialize the card and display some image. If the card blow up a fuse on your friend's PSU the second you push start button then its 99% shorted, dead, fried...
Can you use some kind of an old GPU (one that you dont care about) to install on your PC and confirm if its working or not?


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## Frostified (Nov 18, 2019)

Zach_01 said:


> First thought, before you write the specs, was also the PSU like all others responded... But now seeing the them I suspect that the GPU has gone. The CX line PSUs from Corsair is not the best but I cant imagine a 750W PSU not handling a 400~450W PC.
> 
> The 980Ti is a high power draw (~250W) gpu and has a reccomended minimum of 600W PSU but this is only for gaming. A 500W PSU for sure can at least initialize the card and display some image. If the card blow up a fuse on your friend's PSU the second you push start button then its 99% shorted, dead, fried...
> Can you use some kind of an old GPU (one that you dont care about) to install on your PC and confirm if its working or not?



Thanks a lot for the response. I did use the said other PC's old GTX 770 to try boot up my PC but it starts up and tuns off instantly after 2 seconds with no beep to indicate the successful boot. I thought my Hard Drive might have been a casualty as well but even after changing it, same thing happened. Maybe the GPU killed my motherboard as well when it shorted?


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## Zach_01 (Nov 18, 2019)

Frostified said:


> Thanks a lot for the response.* I did use the said other PC's old GTX 770 to try boot up my PC but it starts up and tuns off instantly after 2 seconds with no beep to indicate the successful boot*. I thought my Hard Drive might have been a casualty as well but even after changing it, same thing happened. Maybe the GPU killed my motherboard as well when it shorted?


Things are difficult at this point and you need to test every component one by one to find what survived or not. keep that 770 and next one to change is the PSU.
If you install another known working PSU and the same thing happens then chances that the board has gone too is close to max. And who knows about the rest... CPU, RAM...

PSU checking...










And if you have a voltage meter...


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## Frostified (Nov 18, 2019)

Zach_01 said:


> Things are difficult at this point and you need to test every component one by one to find what survived or not. keep that 770 and next one to change is the PSU.
> If you install another known working PSU and the same thing happens then chances that the board has gone too is close to max. And who knows about the rest... CPU, RAM...



I see. I will try the links you sent once I get home later today. I ordered a new motherboard which if I don't end up needing will probably give to a friend. I think it should be fine after changing the motherboard, but I will be sure to check my PSU and test with a different one. If that doesn't solve the problem, I don't know what will. I appreciate the help a ton.


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## eidairaman1 (Nov 18, 2019)

Where do you live?


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## Zach_01 (Nov 18, 2019)

eidairaman1 said:


> Where do you live?


Worry about power grid/network voltages?


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## eidairaman1 (Nov 18, 2019)

Zach_01 said:


> Worry about power grid/network voltages?



Exactly especially with a cx psu


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## 64K (Nov 18, 2019)

I agree with the others. I think it's your PSU. Swap in the other PSU and see if it's still doing this. I had a PSU go bad on me and it was turning off and on about every minute. Mine was a 750 watt Corsair HX and I was using a 980 Ti too with a 3570k CPU. I was nowhere near the capacity of the unit. It was just a faulty PSU after a few years.


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## Frostified (Nov 18, 2019)

eidairaman1 said:


> Where do you live?



United Kingdom, England. Shouldn't be anything out of the ordinary.


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## 64K (Nov 18, 2019)

@Frostified when you put that different PSU in your rig let us know if that fixes the issue.


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## Frostified (Nov 18, 2019)

64K said:


> @Frostified when you put that different PSU in your rig let us know if that fixes the issue.



Right. You lads were all correct. I put in the new motherboard I bought and it didn't change anything. So I changed the PSU aaand... You guessed it. It's working! I really appreciate y'all's help.


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## eidairaman1 (Nov 18, 2019)

Frostified said:


> Right. You lads were all correct. I put in the new motherboard I bought and it didn't change anything. So I changed the PSU aaand... You guessed it. It's working! I really appreciate y'all's help.



Now is old motherboard still good?


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## Frostified (Nov 18, 2019)

eidairaman1 said:


> Now is old motherboard still good?



Yep. I will find a use for it. It's still nice and healthy.


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## eidairaman1 (Nov 19, 2019)

Heck id get money back tbf


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## FreedomEclipse (Nov 19, 2019)

In my own experience. those CX power supplies are absolute *JUNK*. Some people have had great success with them but Ive had to replace a few for clients as well as heard stories about bad power supplies like yours. More than enough to stick with the RM/RMX line or stick with Seasonic power supplies.


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## DeathtoGnomes (Nov 19, 2019)

FreedomEclipse said:


> In my own experience. those CX power supplies are absolute *JUNK*. Some people have had great success with them but Ive had to replace a few for clients as well as heard stories about bad power supplies like yours. More than enough to stick with the RM/RMX line or stick with Seasonic power supplies.


agreed. 

For future reference, my sig has a link to a PSU ratings list, the CX ranks worse the older it is, at best its only rates a C level, basic entry level.


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## E-curbi (Nov 19, 2019)

This happened to me, it was a faulty APC power strip, that had a grounding issue, that led to faulty bios flashing. With a new motherboard and the power strip had worked just fine for 24months, so you would 1st guess - motherboard. NOPE.

The diagnosis was made by switching off the mobo, and the board not completely powering down for 2-3minutes, sometimes longer = grounding issue.

A motherboard and PSU with healthy grounding will discharge all power in 5-6seconds.

Check to see if that is what's going on.

At least one mobo variable you can possibly eliminate from your troubleshooting list.


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## FreedomEclipse (Nov 19, 2019)

DeathtoGnomes said:


> agreed.
> 
> For future reference, my sig has a link to a PSU ratings list, the CX ranks worse the older it is, at best its only rates a C level, basic entry level.



I mean the sad thing about it? CWT make some of the CX line alongside Great Wall. CWT made the CX750. CWT make most of corsairs PSUs (over 90%) Even some pretty high end ones. CWT make some of the RM and all the RMX series of power supplies and the RM/RMX line are known as some of the best in terms of reliability. Where does it all go wrong??? I can only assume that corsair really cheaped out on the components or the overall circuit design inside is pretty janky.

CWT are capable of making good PSUs, so why is the CX line so unreliable?


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## DeathtoGnomes (Nov 19, 2019)

FreedomEclipse said:


> Where does it all go wrong???


That, sir, is the million dollar question.

I'd guess they outsource locally too.


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## Frostified (Nov 19, 2019)

Unfortunately I am kind of tight on money since I also bought a new GPU so I went with a CX again. It lasted me 3 years so I'm not complaining.


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## Zach_01 (Nov 19, 2019)

Man... why the same?
3 years is very short period for a PSU. And a proper PSU, when it dies, must not take with it other components. This is unacceptable to me.
Though its not sure if the PSU fried the VGA or the other way around... Could be the other way. Still it shouldn't happen...

CX line from Corsair is the lowest quality from newer tech and CXM and VS lines is old tech.
You could at least go with RM/RMi/RMx. Or even a different brand like EVGA or Seasonic.
HX/HXi and AX/AXi are very nice but way more expensive.
Dont know anything about TX, CSM...

How much did you pay it may I ask? ...and where is your local market?


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## Valantar (Nov 19, 2019)

Frostified said:


> Unfortunately I am kind of tight on money since I also bought a new GPU so I went with a CX again. It lasted me 3 years so I'm not complaining.


It lasted you three years - which is terrible for a PSU - and cost you a $500 GPU. Not worth $500 today of course, but you're still out a tidy sum for anything matching or exceeding its performance. Is that worth it compared to spending £30-40 more on a better PSU? Of course not. You would have been better off going for a cheaper GPU and a better PSU - at least then you would be sure this won't happen again in 2-3 years, and you could focus your money on upgrading the GPU.


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## Frostified (Nov 19, 2019)

Yeah, well. You have a point. I bought a new CXM from Amazon for £80. I really just don't have the money for a higher quality one right now. I checked the price range of S tier and Tier 1 PSUs and it was too much. I will definitely upgrade it and keep the CX as a spare in a month, two or three. I might go EVGA. Also, it was definitely the VGA that killed the PSU. But if you really think it shouldn't happen, I will upgrade soon. 

Right now I got a 1060 6 GB as a placeholder for £150 and I am trying to find a place where they could repair my 980 Ti and hopefully it's not a crazy price. If that doesn't work, I will eventually get a better GPU. I don't really play anything which needs a high end GPU at the moment.


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## FreedomEclipse (Nov 19, 2019)

Good luck finding a place that repairs GPU's. I've never heard of a shop doing it on their own. Its always been a sent off for warranty thing. No shop would have a schematic of a graphics card or any graphics card. There might be a few things a good electrician that is worth his salt can test and have a look at but without schematics he's wasting his time by trying to find the problem if you don't know what it is. 

You're better off contacting the manufacturer and asking for a quote on an out of warranty warranty repair job. It will save you money as getting a good electrician who knows enough to even look at the card won't be cheap. 


For £80 I would of bought an EVGA GQ - I have used many of these in client builds and they are still going strong. Their OEM is FSP which are one of the best players out there even though they tend to be underrated and ignored by people alot because they don't throw tonnes of money into their PR like corsair and other big companies do.


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## Frostified (Nov 19, 2019)

Thanks for the PSU suggestion. I will save it for the future. What's a PSU you recommend for up to £150?

I know there's no official repair services but I know a pretty good electrician and I want him to have a look just in case.I probably won't bother sending it to Nvidia for repair since there is a good chance the price is crazy high. Most likely going to save up for a 1080 after getting some other upgrades like an SSD, GPU liquid cooling and a better PSU.


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## phill (Nov 19, 2019)

Frostified said:


> Yeah, well. You have a point. I bought a new CXM from Amazon for £80. I really just don't have the money for a higher quality one right now. I checked the price range of S tier and Tier 1 PSUs and it was too much. I will definitely upgrade it and keep the CX as a spare in a month, two or three. I might go EVGA. Also, it was definitely the VGA that killed the PSU. But if you really think it shouldn't happen, I will upgrade soon.
> 
> Right now I got a 1060 6 GB as a placeholder for £150 and I am trying to find a place where they could repair my 980 Ti and hopefully it's not a crazy price. If that doesn't work, I will eventually get a better GPU. I don't really play anything which needs a high end GPU at the moment.



For that money you can buy an EVGA G+ 650w unit and that is a load better than the Corsair   I have two 650w's and two 850w models and they are brilliant units.  I believe Scan or Ebuyer sales them at a decent price..  

As for the GPU, the G Gaming series of Gigabyte cards haven't for me been a good card to use at all...  Stick with something like an EVGA SC or FTW or a MSI Gaming X model.  Those coolers are amazing and much better than the Gigabyte side of things.  

EVGA G+ 650w PSU  Buy it   £80, £10 off


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## Zach_01 (Nov 19, 2019)

Frostified said:


> Thanks for the PSU suggestion. I will save it for the future. What's a PSU you recommend for up to *£150*?


...or this for a ~100£





						EVGA G3 750 W 80+ Gold Certified Fully Modular ATX Power Supply
					






					uk.pcpartpicker.com
				




What will be you PC configuration after all the replacements for long term usage?


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## Komshija (Nov 19, 2019)

I would first check whether all cables are OK and connectors are seated properly. Update motherboard BIOS. You can start and run the system without a GPU because i7 6700K has iGPU - before it boots enter the BIOS and find sub-menu where you can select between PEG (real GPU) and IGP (integrated GPU). Select IPG, save and exit BIOS. This particular menu should be somewhere in advanced options under graphic peripherals or something similar. Thus you can find out whether the rest of the components work. Check voltages with HWinfo.


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## Frostified (Nov 19, 2019)

Zach_01 said:


> ...or this for a ~100£
> 
> 
> 
> ...



Okay... Damn. I actually did fuck up.

Specs I will have:

CPU: I7 6700k
Motherboard: z390 A Pro
GPU: GTX 1080 MSI/EVGA (not sure yet)
PSU: Something high on the PSU tier list. Maybe your suggestion.
Case: NZXT H510
GPU Luqid Cooling: Probably going for CoolerMaster but I haven't looked into it that much yet.


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## Zach_01 (Nov 19, 2019)

I would say that a 650W will do the job just fine for this, but that particular EVGA SuperNova G3 750W is the same price with 650W model... so...






						Choose A Power Supply
					






					uk.pcpartpicker.com


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## Frostified (Nov 19, 2019)

Komshija said:


> I would first check whether all cables are OK and connectors are seated properly. Update motherboard BIOS. You can start and run the system without a GPU because i7 6700K has iGPU - before it boots enter the BIOS and find sub-menu where you can select between PEG (real GPU) and IGP (integrated GPU). Select IPG, save and exit BIOS. This particular menu should be somewhere in advanced options under graphic peripherals or something similar. Thus you can find out whether the rest of the components work. Check voltages with HWinfo.



I actually didn't know this. I thanks a lot. Now I can use my PC 2 days before my GPU comes.


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## DeathtoGnomes (Nov 19, 2019)

did you not check the PSU tier list in my signature?


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## Zach_01 (Nov 19, 2019)

DeathtoGnomes said:


> did you not check the PSU tier list in my signature?


Is the EVGA G3 that bad? People keep recommending it... That list is for the specific ones or all the line? I mean the G3 550W, 650W, 750W...


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## EarthDog (Nov 19, 2019)

Zach_01 said:


> Is the EVGA G3 that bad? People keep recommending it... That list is for the specific ones or all the line? I mean the G3 550W, 650W, 750W...


Not sure he was talking to you, but maybe in general the OP ( people should quote the person you are talking to unless it is the post above) as the G3 PSUs (that 750W you linked) is fine...550W too...






						EVGA SuperNOVA 750 G3 Power Supply – Page 6 – JonnyGURU.com
					






					www.jonnyguru.com
				











						EVGA SuperNOVA 550W G3 Power Supply Review - PC Perspective
					

EVGA SuperNOVA 550W G3 Power Supply Review Introduction




					pcper.com


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## Zach_01 (Nov 19, 2019)

EarthDog said:


> Not sure he was talking to you, but maybe in general the OP ( people should quote the person you are talking to unless it is the post above) as the G3 PSUs (that 750W you linked) is fine...550W too...


I'm quiet sure he was not talking to me but the OP. I just ask because I saw the G3 550W on D-Tier list, so...


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## Valantar (Nov 20, 2019)

Frostified said:


> Yeah, well. You have a point. I bought a new CXM from Amazon for £80. I really just don't have the money for a higher quality one right now. I checked the price range of S tier and Tier 1 PSUs and it was too much. I will definitely upgrade it and keep the CX as a spare in a month, two or three. I might go EVGA. Also, it was definitely the VGA that killed the PSU. But if you really think it shouldn't happen, I will upgrade soon.
> 
> Right now I got a 1060 6 GB as a placeholder for £150 and I am trying to find a place where they could repair my 980 Ti and hopefully it's not a crazy price. If that doesn't work, I will eventually get a better GPU. I don't really play anything which needs a high end GPU at the moment.





Frostified said:


> Okay... Damn. I actually did fuck up.
> 
> Specs I will have:
> 
> ...


You are demonstrating a classic example of the PSU output fallacy: you've been paying for wattage you don't need rather than quality, and all you have to show for it is a dead GPU and PSU. A PC like that will - in a worst-case scenario - maybe pull 400W from the wall. My system with a much more power-hungry R9 Fury X and relatively comparable Ryzen 5 1600X pulls around 400W at the wall during normal gaming. If I were to guess you would probably be closer to 300W than 400W in actual in-game power draw. Also, remember that PSU ratings are for output, while at-wall power is input power which includes the efficiency losses from your PSU. In other words, my 400W under load with an 80+ Gold PSU is likely somewhere around 357W internal draw.

This is an old mode of thinking that was common (and useful) around a decade ago, when PSU ratings where generally BS, and you couldn't trust a PSU to deliver its rated output. This is no longer the case today, at least for decent quality PSUs. Also, component manufacturer "minimum PSU" ratings are equally BS, or at least padded to infinity and beyond, as they want to ensure that nobody blows up their new component due to having a shitty, low-end GPU or having a million HDDs or other power-hungry hardware. Real-world power draw from reviews is a _far_ better indicator of PSU needs than a manufacturer spec. AnandTech measured 335W at-wall in their 1080FE review, and that's with an old overclocked HEDT CPU (i7-4960X).

There are tons of good PSU choices with good quality and reasonable outputs (500-750W) these days. Even 750W is complete overkill for any non-HEDT PC unless you are doing ridiculous overclocking (though even a maxed out 9900K and 2080Ti would struggle to exceed 600W in a power virus test). As such, buying a lower output, higher quality PSU is the only reasonable approach.

Of course there are arguments for having a higher total output, such as having room to upgrade (largely moot, as >300W GPUs aren't likely to become common any time soon, and 550W is plenty for >99% of hardware combinations), and noise in terms of having a higher rated "semi-passive" mode (though any 135mm or 140mm fan of decent quality will be inaudible over a common GPU). The chief reason for PSU overprovisioning is to counteract capacitor aging, as the max output is likely to drop a bit over the lifetime of the PSU. In other words, buying a 450W PSU for a PC routinely pulling up to 400W will work, but might not work for five years. Boosting that number to 550 or 650 gives a decent safety margin. But even there, 750W is overkill.

People need to stop making stupid PSU buying decisions.

Also, I seriously doubt your GPU killed your PSU - the GPU might have died first, but unless id had a serious manufacturing fault, the PSU is the most likely culprit as to why it failed in the first place.


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## Frostified (Nov 20, 2019)

Valantar said:


> You are demonstrating a classic example of the PSU output fallacy: you've been paying for wattage you don't need rather than quality, and all you have to show for it is a dead GPU and PSU. A PC like that will - in a worst-case scenario - maybe pull 400W from the wall. My system with a much more power-hungry R9 Fury X and relatively comparable Ryzen 5 1600X pulls around 400W at the wall during normal gaming. If I were to guess you would probably be closer to 300W than 400W in actual in-game power draw. Also, remember that PSU ratings are for output, while at-wall power is input power which includes the efficiency losses from your PSU. In other words, my 400W under load with an 80+ Gold PSU is likely somewhere around 357W internal draw.
> 
> This is an old mode of thinking that was common (and useful) around a decade ago, when PSU ratings where generally BS, and you couldn't trust a PSU to deliver its rated output. This is no longer the case today, at least for decent quality PSUs. Also, component manufacturer "minimum PSU" ratings are equally BS, or at least padded to infinity and beyond, as they want to ensure that nobody blows up their new component due to having a shitty, low-end GPU or having a million HDDs or other power-hungry hardware. Real-world power draw from reviews is a _far_ better indicator of PSU needs than a manufacturer spec. AnandTech measured 335W at-wall in their 1080FE review, and that's with an old overclocked HEDT CPU (i7-4960X).
> 
> ...



Wow... Well, this is the first time I'm hearing this. I could have saved myself a lot of money. Better late than never I guess.


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## Valantar (Nov 20, 2019)

Frostified said:


> Wow... Well, this is the first time I'm hearing this. I could have saved myself a lot of money. Better late than never I guess.


Sadly, a lot of people (even on these forums) keep recommending massively overpowered PSUs for no reason other than that it used to be smart back in the day. Heck,  the entire >1000W PSU market (outside of mining, which is largely dead anyhow, and extreme LN2 overclocking) is held up by people buying stupidly overkill hardware. 750W is sufficient for most _dual _GPU setups today, and the most common single GPU setups (say, a GTX 1660 or RTX 2060 with an SSD, an HDD, 16GB of RAM, some RGB and a reasonable CPU around 95W) would struggle to exceed 300W internal power draw under normal gaming usage. PC components these days are very, very power efficient, and due to the limitation of modern process technologies, they don't generally scale all that much when overclocked either. The days of 500W overclocked GPUs are long gone. There are of course exceptions, like the 9900K (which, to be frank, is a power hog even at "stock" on most motherboards), but those are the exception, not the norm. Also, it's worthwhile to remember that no normal workload stresses the CPU and GPU both at 100%. Gaming is generally 100% GPU and a medium CPU load. Rendering generally stresses either GPU or CPU 100%, but rarely both. And so on.

My rule for calculating the PSU requirements of a build go roughly like this: real world power CPU power draw from a review + real world GPU power draw from a review + 15-25W for the motherboard and RAM, 5W for each SSD, 10W for each 3.5" HDD + a couple of watts per fan + 5W for each AIO pump + whatever is needed for any other add-in-cards, components or power-hungry periperhals (usually not applicable). If overclocking, look at power draw numbers from someone overclocking the same component, and perhaps add 20% for safety/bad luck in the silicon lottery. Sum that all up, then add 20% to the total for some margin (as menitoned above, running your PSU for extended periods at 100% load will shorten its lifespan), and you're good to go. Not all these numbers reflect actual max power draw for each component (NVMe SSDs often peak at 5-7W, some fans draw 5W or more; 3.5" HDDs can peak at 15 or even 20W during spin-up), but they are more than sufficient for calculating the sum total power draw of the PC under normal usage.

So, for your proposed hardware (I'm assuming you mean the i7-9700K, as a 6700K can't run on a Z390 board):

i7-9700K: TPU says 41W idle and 180W running Cinebench nT for the full system on a Z390 board, so ~*140W*. As this is far above TDP, this test result likely reflects MCE or similar unlocks, and is reliable. Overclocked to 5.1 GHz the 180W number jumps to 237W, so the CPU draw jumps to about *200W *total. These full-system power measurements include PSU losses, so these numbers are perfectly safe to work with.
(in case you actually mean the i7-6700K, but with a compatible motherboard: Hexus says 23W idle and 99W video encoding for the full system on a Z170 board, so ~80W stock, but this varies with motherboard power settings, so let's stick to the *91W* TDP. Don't have overclocked numbers for this.)
GTX 1080: Let's assume you're going for an overclocked model, so I'm basing my numbers on the TPU Zotac AMP! Extreme review, which measures out at 245W _peak _gaming, and 222W average gaming. Comparable numbers for the non-overclocked FE card are 166W and 184W, so this is pushing it for a 1080. Still, let's say *245W *for safety, or *190W *if running a lower end card at stock clocks.
Cooling: if you're going for an AIO on your GPU, you'll likely have one on your CPU too, so *10W *for pumps, and let's say *15W *for four 120mm fans.
Motherboard and RAM: *25W*. This is a rough estimate, but unless your motherboard has something crazy like 10GbE networking, or you're running >4000MT/s RAM at 1.5V or more, it will do.
RGB? I'm guessing yes, so another *10W* for that.
You didn't mention storage, so I'm assuming the relatively standard 1 SSD (*5W*) + 1 HDD (*10W*). 
That leaves us with a total of either *486W *(405W+20%, 9700K stock + 1080 stock), or *624W *(520W+20%, 9700K OC + 1080 OC). In other words a 500 or 550W PSU would be perfectly fine for the former configuration, and a 650W one for the latter. If you meant the 6700K, subtract 60W from each number. Also note that even these numbers are overblown: adding up power draws like this _is not how power draw in PCs actually works_. As said before, no normal consumer workload will stress your CPU _and_ GPU to 100%, so these numbers being based on max per-component power draw for the key components means significant built-in safety margins even before the added 20% - the 20% is for longevity, meaning your PSU can age to where it loses 20% of its output capacity (which will take many, many years for a good unit) and still handle your setup just fine. To add some perspective to this: TPU's 9700K review has full-system power measurements while gaming with a 1080 Ti, and they hit *340W stock or 376W when overclocked to 5.1 GHz*. At the wall, including PSU losses. And that's with a significantly more power hungry GPU than the regular 1080.


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## Bones (Nov 20, 2019)

All I can say is I normally tend to overspec my PSU's by around 10-20% based on wattage demand, this way I don't have to worry about it running at or close to 100% all the time which isn't great for one. Nominal operation is for one to be loaded around 80% of it's rated wattage on average, not too much and yet it's not wasting money on something you really don't need based on cost to get. I've never had a PSU go out (Yet) except for one waaaay back that was defective - That was well before I got into OC'ing stuff.
Every PSU I've had aside from that one still works to this day just fine.

Also helps in that if you decide to carry the unit over to a new build chances are it will be OK for that too.

Now..... I will admit with this build I'm typing on ATM it's got a 1600W unit in use and yes it's been used for Extreme OC'ing before. However since I already had two of these PSU's I just popped one in here instead of having to buy another and letting the other 1600W unit do the XOC thing.
If that one ever goes out I'll still have this one to run with all that and will get something more mundane for this build.


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## Frostified (Nov 20, 2019)

Valantar said:


> Sadly, a lot of people (even on these forums) keep recommending massively overpowered PSUs for no reason other than that it used to be smart back in the day. Heck,  the entire >1000W PSU market (outside of mining, which is largely dead anyhow, and extreme LN2 overclocking) is held up by people buying stupidly overkill hardware. 750W is sufficient for most _dual _GPU setups today, and the most common single GPU setups (say, a GTX 1660 or RTX 2060 with an SSD, an HDD, 16GB of RAM, some RGB and a reasonable CPU around 95W) would struggle to exceed 300W internal power draw under normal gaming usage. PC components these days are very, very power efficient, and due to the limitation of modern process technologies, they don't generally scale all that much when overclocked either. The days of 500W overclocked GPUs are long gone. There are of course exceptions, like the 9900K (which, to be frank, is a power hog even at "stock" on most motherboards), but those are the exception, not the norm. Also, it's worthwhile to remember that no normal workload stresses the CPU and GPU both at 100%. Gaming is generally 100% GPU and a medium CPU load. Rendering generally stresses either GPU or CPU 100%, but rarely both. And so on.
> 
> My rule for calculating the PSU requirements of a build go roughly like this: real world power CPU power draw from a review + real world GPU power draw from a review + 15-25W for the motherboard and RAM, 5W for each SSD, 10W for each 3.5" HDD + a couple of watts per fan + 5W for each AIO pump + whatever is needed for any other add-in-cards, components or power-hungry periperhals (usually not applicable). If overclocking, look at power draw numbers from someone overclocking the same component, and perhaps add 20% for safety/bad luck in the silicon lottery. Sum that all up, then add 20% to the total for some margin (as menitoned above, running your PSU for extended periods at 100% load will shorten its lifespan), and you're good to go. Not all these numbers reflect actual max power draw for each component (NVMe SSDs often peak at 5-7W, some fans draw 5W or more; 3.5" HDDs can peak at 15 or even 20W during spin-up), but they are more than sufficient for calculating the sum total power draw of the PC under normal usage.
> 
> ...



 I am definitely saving your reply somewhere to use as reference in the future. I suppose for the setup I have right now I probably don't even need 400W then. i7 6700K, 1060 6GB, z170, 8 GB RAM, CPU pump. Also, yeah I got confused. I will be getting a 9K CPU for the z390 board in the future. Right now I'm staying with a z170.

Won't be making this mistake again in that case. Thanks for the words of wisdom.


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## Valantar (Nov 20, 2019)

Frostified said:


> I am definitely saving your reply somewhere to use as reference in the future. I suppose for the setup I have right now I probably don't even need 400W then. i7 6700K, 1060 6GB, z170, 8 GB RAM, CPU pump. Also, yeah I got confused. I will be getting a 9K CPU for the z390 board in the future. Right now I'm staying with a z170.
> 
> Won't be making this mistake again in that case. Thanks for the words of wisdom.


No problem, that's what the forums are for 

The GTX 1060 is a very efficient card, so if I were to guesstimate I would say your current setup probably consumes around 250W at the wall while gaming. As such, yes, a good quality 400W PSU would be entirely sufficient - it's just that there are sadly very very few high quality units in that wattage range. Quality units tend to start at 550W or so - which is still entirely reasonable, and allows for headroom to upgrade past your current ~120W GPU. And thankfully most PSU manufacturers are starting to flesh out their lower wattage ranges - a few years ago it wasn't uncommon that you _had_ to buy 750W or more if you wanted a modern PSU design with good efficiency.


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## eidairaman1 (Nov 20, 2019)

Frostified said:


> Unfortunately I am kind of tight on money since I also bought a new GPU so I went with a CX again. It lasted me 3 years so I'm not complaining.




Youre asking for it!

I would of sent the new motherboard back.


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## skizzo (Nov 20, 2019)

Bones said:


> Nominal operation is for one to be loaded around 80% of it's rated wattage on average, not too much and yet it's not wasting money on something you really don't need based on cost to get.



the nominal/optimal load for PSU's are 50%, ie. where they are the most efficient.


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## Valantar (Nov 20, 2019)

skizzo said:


> the nominal/optimal load for PSU's are 50%, ie. where they are the most efficient.


Given that modern 80+ Gold or above designs vary in efficiency by a few percent between 20 and 100% load, it's hard to definitively say they have an "optimal" load at all. And I don't mean only high-end designs - look at something like the Bitfenix Formula Gold 750W, which TPU reviewed back in 2017, which should be reasonably representative of a middle-of-the-pack 80+ Gold design these days.





While efficiency drops precariously below 20% load (which matters little in terms of PSU wear or lifespan simply because the thermal output at those low loads are small anyhow, but still is worth improving  - and is improving in high-end units thanks to 80+ Titanium finally implementing a 10% load efficiency requirement), it hits >89.5% at 20% load (150W), slightly above 92% at ~350W, and slowly dips down to 90% again at ~825W, or a 10% overload. To sum up, there's a maximum 3% variance in efficiency when your PC is not idling. Claiming that the 50% point somehow stands out is not really accurate on modern PSUs. A 2-3% variance in efficiency hardly matters at all - it's small enough that the heat output scales pretty much linearly with the load applied throughout this part of the load range.

Beyond that, the nominal load of an X watt PSU is supposed to be X. If it can't handle that output, it should neither be named nor rated to do so. And as seen in most good PSU reviews, modern PSU designs can generally handle higher loads than what their labels say, not lower (though this will likely lead to a shortened lifespan, it should not cause the unit to immediately break). Nobody should recommend a 100% PSU load for extended periods of time, but 80% when gaming is perfectly fine - particularly as you're very unlikely to be gaming 24/7. Even gaming PCs spend the majority of their in-use time idling or on the desktop.


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## EarthDog (Nov 20, 2019)

Valantar said:


> Given that modern 80+ Gold or above designs vary in efficiency by 5-8% between 20 and 100% load, it's hard to definitively say they have an "optimal" load at all.


At most, 3% (for 120V, 4% for 230V). Otherwise it doesn't qualify for the tier rating.


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## Valantar (Nov 20, 2019)

EarthDog said:


> At most, 3%.
> 
> View attachment 137093


Heh, thanks, I just (don't know if it happened before or after your post tho) edited that part to say "a few percent"  I couldn't be bothered to look up a table, so thanks anyhow!


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## EarthDog (Nov 20, 2019)

Valantar said:


> Heh, thanks, I just (don't know if it happened before or after your post tho) edited that part to say "a few percent"  I couldn't be bothered to look up a table, so thanks anyhow!


Your other points remain... just tightening it up a bit.


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## Valantar (Nov 20, 2019)

We're veering a bit OT here, but nonetheless I mocked up a little graph to show just how misleading these cropped/non-zero Y axis efficiency graphs can be, with data approximated from the TPU graph above. Mostly meant as a response to @skizzo, but we can all need the reminder once in a while. The first is the type of graph you see in reviews:




The second is the same graph, just with 0% efficiency plotted in at 0 Watts to force Excel to not crop the Y axis.




That ... is essentially a flat line past 20% load. 

While they make the relatively small differences between units easier to understand, these types of graphs nonetheless work to perpetuate the false belief that modern PSUs have dramatic changes in efficiency within their rated load range. Sure, 0-20% load is a bit of a free-for-all, but even there most 80+ Gold units exceed 80%. And beyond 20% load, the graph is essentially flat. It's time to stop this "50% load is what you should aim for" nonsense.


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## skizzo (Nov 20, 2019)

Valantar said:


> Given that modern 80+ Gold or above designs vary in efficiency by a few percent between 20 and 100% load, it's hard to definitively say they have an "optimal" load at all. And I don't mean only high-end designs - look at something like the Bitfenix Formula Gold 750W, which TPU reviewed back in 2017, which should be reasonably representative of a middle-of-the-pack 80+ Gold design these days.
> 
> 
> 
> ...



I can't disagree with your response here, it's valid, but isn't mine also? Which seems to be supported by that graph. The absolute most efficient load on that PSU is between 300W and 400W which aligns with 50% of power rating which is around 375W on 750W rated PSU. So I think perhaps I used too much of an absolute statement the first time or referred to the wrong thing. I am referring to what I think is supported by that graph....the PSU is at its highest effiency at around a 50% load of what it is rated for. For example, a 1000W PSU would be most efficient around 500W load



Valantar said:


> We're veering a bit OT here, but nonetheless I mocked up a little graph to show just how misleading these cropped/non-zero Y axis efficiency graphs can be, with data approximated from the TPU graph above. Mostly meant as a response to @skizzo, but we can all need the reminder once in a while. The first is the type of graph you see in reviews:
> 
> 
> 
> ...



OK I have never read about or seen things like that 2nd graph you attached. Honestly having a difficult time grasping the difference between the two graphs, or i should say, what they are measuring differently to produce such a dramatic different curve.  If both measure efficiency vs load I'm having trouble understanding your explanation on the difference. Sorry, I'm the slow guy who needs a "talk to me slow" or "can you repeat that" again kinda explanation lol

edit, so I get what you mean about your statement saying the measurable difference is so small it doesn't matter "in real world scenarios". ie running at 80% load might cost a few % less efficient, it's so small it's not going to be very noticeable to the user if the PSU will fail earlier because of this use case. If that is what you are getting at, I do understand. but regardless it's still true that technically it is most efficient at around that 50% load range


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## EarthDog (Nov 20, 2019)

skizzo said:


> OK I have never read about or seen things like that 2nd graph you attached. Honestly having a difficult time grasping the difference between the two graphs, or i should say, what they are measuring differently to produce such a dramatic different curve. If both measure efficiency vs load I'm having trouble understanding your explanation on the difference. Sorry, I'm the slow guy who needs a "talk to me slow" or "can you repeat that" again kinda explanation lol


Look at the left side of the graphs.. Notice one starts at zero while the other starts at 78%? With the latter, the curve is more pronounced throughout the power range (20%-100%) due to the axis values being cropped.

If you look at the first graph and do not notice/take into account the axis values, then the curve looks a lot more 'peaky' than flat like it is (literally a 3% difference for 120V). Shrinking the range increases the granularity of the data and extenuates the curve.



Valantar said:


> It's time to stop this "50% load is what you should aim for" nonsense.


THIS.



skizzo said:


> edit, so I get what you mean about your statement saying the measurable difference is so small it doesn't matter "in real world scenarios". ie running at 60% load might cost a few % less effient, it's so small it's not going to be very noticeable to the user if the PSU will fail earlier because of this use case. If that is what you are getting at, I do understand.


Yeah, while I understand the thinking behind it (running a PSU at less power is less stress on the components), users are already building in plenty (if not too much) headroom already. I fully expect any quality PSU to be able to output its nameplate values for at least the life of its warranty. Of course, nobody does or should run 100% all the time, but to lop it in half for efficiency sake or a longer life is really splitting a split hair. Save your 9royal you, not you specifically) damn money and get an appropriately sized unit instead. I stick between 60-80% use, closer to the latter (I run a 750W unit and a 7960x (16/32t at 4.4. GHz along with a RTX 2080 Ti - also overclocked... my fan doesn't even spin up!).


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## Bones (Nov 20, 2019)

skizzo said:


> the nominal/optimal load for PSU's are 50%, ie. where they are the most efficient.


I have to disagree but hey, to each his/her own right?
Why of course.


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## lexluthermiester (Nov 20, 2019)

I think this thread has run it's course. The OP solved their problem on the first page and here things are...


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## EarthDog (Nov 20, 2019)

lexluthermiester said:


> I think this thread has run it's course. The OP solved their problem on the first page and here things are...


The OP has been responding to the great information here as of this morning... his issue is resolved, yes, then slizzo chimed in... (a repeat of info shared recently here at this site)..lol.


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## Tatty_One (Nov 20, 2019)

Thanks everybody, thread...………………….


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