# My computer turns on and back off in a split second!



## V8VANTAGE (Aug 31, 2012)

Hi,

I posted yesterday, but that was in someone elses thread and I didn't want to hijack it so i've created my own thread. It seems my issue is actually different.

For those who haven't read the other thread, the problem is that for some reason, my main pc switches on and then a split second later switches off. Blink and you'll miss it. Like many on here that have had the same problem, I thought my PSU had died. So I went ahead just now and see if it powers up my TV recorder rig/HTPC which usually just runs on a 200w Hiper supply. I just plugged in the bare essentials, and boom, it works absolutly fine. Therefore, that basically rules the power supply out in my mind. 

If it helps, my GPU acted a bit weird yesterday for the first time since I've owned it. Whilst I was browsing the web for about 8-10 seconds, the screen went black. Then it came back and said that the Nvidia driver stopped responding and has recovered. I am not sure if the graphics card is to blame for the issue i have now. I would test it in my HTPC only it doesn't fit in the case! Or could this still be the power supply because my HTPC consumes less than 150w so the psu isn't under stress?

What else could it be? I'm stumped now!

Here are the complete specs of the 2 machines.

========Gaming Rig========
*Motherboard* - Asus P8P67 ATX R3
*Processor* - Intel Core i5 2500k
*Processor cooler *- Thermalright Venomous X with 1 Enermax Apollish and 1 Antec 3 speed fan
*RAM* - 2x4GB (8GB) DDR3 1600mhz HyperX Genesis Grey
*Graphics Card *- inno3D Hawk Edition Nvidia Geforce GTX470 1.5gb VRAM
*Hard drives *- Western Digital Caviar Black 1TB
                   Western Digital Caviar Black 500GB
                    Corsair Force F60 60GB SSD
*Case* - Antec 900 (mk1)
*Case accessories*: 120mm Akasa cold cathode lighting kit
                                3x 120mm Enermax Apollish case fans 
                                1x 200mm Antec 900 3 speed fan
                                Aerocool V12xt Fan Controller
*PSU* - Antec Earthwatts 650w 80plus

=============HTPC Rig==============
*Processor* - Intel Core i3 2100
*Processor cooler *- Akasa K25 ultra slim processor cooler
*RAM* - 2x2gb (4gb) Kingston HyperX Blu DDR3 1333mhz
*Graphics Card *- Intergrated Intel HD 3000
*Hard drives *- Western Digital Scorpio Blue 500GB
                   Intel 40GB SSD
*Case* - Hiper HMC2K53 ultra slim case
*Power Supply* - Hiper 200w micro power supply

Sorry for wall of text but I wanted to cover all bases that I could think of.


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## Jetster (Aug 31, 2012)

So you need to do more trouble shooting techniques. One by one taking the thing apart. After removing a component try to start it up and see if it stays running. Something is causing a problem. May be a memory stick my be a CPU not seated properly. May be your fan controller.

And I took it that its not starting by itself. You turn it on and it shutting down by itself right?

Eventually you will get down to just the PSU, motherboard, CPU, GPU one stick of ram and no case. Does it stay running now?


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## V8VANTAGE (Aug 31, 2012)

Yeah sorry for the slight vagueness about the on/off thing. Yes I switch it on with the cases power button and this is what happens. I try and connect up just the bare essentials outside the case on some cardboard. I've read a short causes these problems too so this is what i'm trying next. Thing is though, I haven't touched anything since may last year when I did a major upgrade from a 775 to 1155 based mahine. 

Only thing i've done is 2 months ago I used some canned air and blasted all of the dust out of every crevice and fan and up until yesterday afternoon, everything was great.


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## Jetster (Aug 31, 2012)

Well if you try all that and it still wont post. Try another GPU then RMA the board to ASUS


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## W1zzard (Aug 31, 2012)

> my main pc switches on and then a split second later switches off


it does that by itself or when you press the power button?

when you press the power button and you have a short circuit somewhere the psu will cut off power instantly

to "reset" the psu so it will turn on again, re-plug the atx mobo connector


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## V8VANTAGE (Aug 31, 2012)

Right, I have left my motherboard in, and have just plugged the motherboard back in with the same 2 sticks of ram, same cpu and everything. Unfortunatly the P8P67 board doesn't have graphics outputs so I can't try intergrated graphics. However, I turned it on and everything runs and it looks like its posting because I don't get any red error lights on the board only the one in the corner which goes on and off after a second as it always has done. No more cutting out straight away. So now, is the problem still the power supply? I mean it has enough life in it to power a basic PC but when the GTX 470 is plugged in it doesn't work or could it be the GTX 470 itself at fault?


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## W1zzard (Aug 31, 2012)

try the gtx 470 without pcie power cable, probably wont boot but you can check if it still short circuits


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## V8VANTAGE (Aug 31, 2012)

Right, plugged it in to the motherboard. PC turns on fine and doesn't cut out.


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## Jetster (Aug 31, 2012)

V8VANTAGE said:


> Right, I have left my motherboard in, and have just plugged the motherboard back in with the same 2 sticks of ram, same cpu and everything. Unfortunatly the P8P67 board doesn't have graphics outputs so I can't try intergrated graphics. However, I turned it on and everything runs and it looks like its posting because I don't get any red error lights on the board only the one in the corner which goes on and off after a second as it always has done. No more cutting out straight away. So now, is the problem still the power supply? I mean it has enough life in it to power a basic PC but when the GTX 470 is plugged in it doesn't work or could it be the GTX 470 itself at fault?



Doesn't mean anything. You need to take the MB out of the case and get a cheep GPU and try it. One stick of ram. If it post then its your GPU or PSU not the MB. If still not the its your MB


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## V8VANTAGE (Aug 31, 2012)

Ok, I've plugged the GTX 470s two 6 pin connectors and turned it on. It seems to work.It shows the Asus splash screen then it says Operating System Not Found, so I couldn't boot it into windows since my Hard drives/SSD are not plugged in and neither are the case fans. 

Whatever it was it seems to be ok now, although I'm still not discounting the possibility that the 470 or psu is on its last legs since the black screen problem yesterday. I didnt mention it before but just lately games have not been running as well as I remember. GTAIV 1.0.0.7 runs between 10 and 40fps whereas before it was really smooth. After about half an hour the game starts to not load high res textures and roads disappear. Some will freeze/crash when they didnt before at random. 

Time to plug it all in and pray its all going to be fine I guess?


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## W1zzard (Aug 31, 2012)

yep. these shorts usually happen between some hardware and case metal, maybe a screw fell down or something


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## Jetster (Aug 31, 2012)

Good. Just put it together one peace at a time and check it to see if you can go to the BIOS. That will help you fine what was shorting it. Good luck


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## V8VANTAGE (Aug 31, 2012)

I'm back. I'm pleased to report that I'm now typing this on my gaming rig. It survived. I don't know what caused the problem in the first place. Only thing the system is overall slower than what it used to be. Go figure, but hey, its working.

Many thanks to those who helped me out


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## eidairaman1 (Aug 31, 2012)

V8VANTAGE said:


> I'm back. I'm pleased to report that I'm now typing this on my gaming rig. It survived. I don't know what caused the problem in the first place. Only thing the system is overall slower than what it used to be. Go figure, but hey, its working.
> 
> Many thanks to those who helped me out



electron creep/migration


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