# Computer powers on and off in a loop, what is the cause?



## mod2max (Oct 26, 2011)

Hi all,

*Problem:* Computer wont POST and worse. (When you press the power button, it powers up for something like 1 second then turns off. It will do this as if it is stuck in a loop until you turn the power off at the wall)

*When did this happen:* I turned my computer off on Tuesday night, went to turn it on Wednesday morning (today) and thats when this problem started. Something has happnened over night but we've had good weather so no chance or a surge from bad weather.

*What has been tried:* I've cleared the CMOS. I've also removed the motherboard from the case to make sure it wasn't shorting out. I've removed all the stuff it doesn't need to be able to POST (Only got the CPU, one stick of RAM and the Graphics Card connected to the motherboard.

*What has been found: *I've tried the Power Supply test where by you place a paper clip in the green wire sock and one of the black wire sockets on the 20/24pin ATX power connector that goes to the motherobard. I've done this test before and the Power Supply powered up, but now this same test does not power on the Power Supply.


I'm thinking it's just the Power Supply that has bit the dust, but I haven't got another one to test with. I may go down to PC World later and buy a new Supply.

Anyone know if OCZ Power Supplies are good or bad?


Thank you so much to anyone who can help!


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## Mussels (Oct 26, 2011)

poqwer supply could be bad. i've also seen this behavior when people forget power connectors such as the 4/8 pin aux CPU power.


OCZ power supplies are mid range. try and get one with less 12V rails, but the same total power (so 4x18A on 12V is less preferable to 2x30A, for example)


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## NdMk2o1o (Oct 26, 2011)

mod2max said:


> Hi all,
> 
> *Problem:* Computer wont POST and worse. (When you press the power button, it powers up for something like 1 second then turns off. It will do this as if it is stuck in a loop until you turn the power off at the wall)
> 
> ...



That sucks, 3 things stick out at me as there is no way of knowing which it is unless you have another rig to test them all in, CPU, Mobo and PSU. If like you say you can just get another from PC-World do that and if it's not that perhaps you can return it? I have an OCZ Fatal1ty in my main rig and have had no problems with it. Only had it 10 months though it has in that time powered a i5 760/860 and i5 2500k with a 470/570 with no issues


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## mod2max (Oct 26, 2011)

Hi NdMk2o1o,

Yeah it does suck... I've had a VERY simliar problem before. I replaced the motherboard which was a Gigabyte GA-X38-DS5 which fixed the problem then. But two things were different... ONE: Tht Gigas**t motherboard had some issue that made the voltages and other electrical related things jump about like no ones business (I thought and was told it was fault of the PSU but turns out it was the mobo), atleast according to SpeedFan and other software. TWO: When I tried the paper clip test on the PSU (the same one I have now) it worked without any issues.

So regardless of anything else thats been killed, it's defo the PSU thats dead now...

And thank you for your feed back on OCZ PSU's, I'm picking up a OCZ 700W Stealth X Stream 2 in less then an hour.


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## Mussels (Oct 26, 2011)

mod2max: you measured voltages with software, thats your problem then and there. do not EVER rely on software voltage readings. they jump around because the sensors are shite, not the voltages themselves.


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## de.das.dude (Oct 26, 2011)

PSU is pooped. there is a thread about good PSUs here. check it out.

Also.... i recently got the corsair GS600. i saw good reviews of this series everywhere so i got it.


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## qubit (Oct 26, 2011)

Dunno if you've got the PSU yet, but Corsair and Seasonic are really good brands too. I've got the Corsair HX850W and it's awesome.


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## mod2max (Oct 26, 2011)

I apologize Mussels for not acknowledging your post as you replyed first I must have justed missed it as I was in quite a rush to get to my local PC World, which for those of you who know the UK... my nearest PC World is Plymouth and I live in Cornwall lol.

Thank you to all that got back to this post, I've now replaced the PSU and am making this post from my computer 

As for better PSU's... I'm happy with what I got tbh (It was a very good price! ...which is not to be expected from PC World), it is 80Plus Bronze certified which is more then can be said for the Zalman piece of s**t I did have.

Again, thanks all


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## DannibusX (Oct 26, 2011)

I had that same thing happen to me with an OCZ GameXStream 700W.  It turns out that I had accidentally goofed the 20/24 pin.  Somehow the 4 pin ended up being inserted second and it was being held just out of contact with the motherboard.

Grats on your new PSU, what did you end up getting?


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## mod2max (Oct 26, 2011)

The 20/24pin you say DannibusX... hmmmmm, when I replaced the PSU earlier both the 20pin and the 4pin were seated pretty solidly cause the 20 holds the 4 in place  (lol) so not exactly sure what caused it to die as suddenly as it did though. 

I got the OCZ 700W StealthXStream 2, and I gotta say it felt more of a quality product then the Zalman did...


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## Bo$$ (Oct 26, 2011)

New OCZ line are excellent i must say


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## qubit (Oct 27, 2011)

mod2max said:


> I apologize Mussels for not acknowledging your post as you replyed first I must have justed missed it as I was in quite a rush to get to my local PC World, which for those of you who know the UK... my nearest PC World is Plymouth and I live in Cornwall lol.
> 
> Thank you to all that got back to this post, I've now replaced the PSU and am making this post from my computer
> 
> ...



Hey, great to hear the story ended well.  And I know what you mean about the shockingly good price. While they're usually very poor value and sell outdated kit, sometimes you get a helluva bargain. In my case it was an Abit AN7 mobo I got in 2004. This cost around £85 in all the usual properly-priced online stores, but was around £60 in PC World. I thought I was dreaming and snapped it up immediately! It's working to this day in a loaner PC for a friend.


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