Random reboots in Windows 7 x64 - PSU issue?

[alltogethernow]

Hello everyone.

I'm having the most odd problem right now. My computer will reboot itself at the most random times. It's as if someone hits the reset button or something, because the computer will simply halt to a black screen, the power seems to hiccup for just a split second, and it boots back through the normal startup splash screen (giving options for entering BIOS and selecting boot device) and into Windows 7 as normal. Windows is of course angry at being shut down improperly. Event viewer shows the following related entry under Kernel-Power, labeled Critical:

"The system has rebooted without cleanly shutting down first. This error could be caused if the system stopped responding, crashed, or lost power unexpectedly."

It happens so randomly that it doesn't seem tied to anything specific. Sometimes it will be good for hours on end. Other times it will only last for a few minutes or less before rebooting. On top of all that, it did it once while inside BIOS.

It's doubly irritating as I just solved a series of problems all caused by bad RAM, and was hoping the computer would finally work. All the old problems stopped, but this random rebooting started. On top of it, the computer once refused to turn on at all until I'd plugged it in to a different outlet. The rebooting still occurs, while that problem does not.

It all makes me think power supply, but it's so bizarre and random I'm hesitant to RMA it just to find out it's, say, the motherboard or something. I'd rather have a more certain notion before I send it back. I'm just not sure how to test it, as I don't own another PSU capable of running the system I can swap in to test.

Specs are as follows:

Intel i7 870
Asus P7P55D-E Mobo
Corsair XMS3 2 x 2GB @ 1600
XFX Radeon HD 5770
Western Digital 1 TB Caviar Black SATA 3 (running @ SATA 2)
LITE-ON DVD Writer Drive
SeaSonic 12SII 520 Watt PSU
3COM PCI(?) ethernet card

Any ideas on what it is causing it, or any suggestions on how to do some testing? I may be able to borrow a friend's PSU, but it'd leave him without a computer, so I'd rather not do that unless it's necessary. Given the length of time that can pass between reboots, it would have to be tested for several days and I don't want to put him out.

Thanks!

 

[seogoat]

I had a problem once with random rebooting and I read around the internet and decided to change my page file size, which was not set correctly. You could also try running your ram at a lower speed to see if it resolves the problem.

 

[alltogethernow]

I'm trying the RAM at 1333 now, we'll see how it goes. But I have my doubts it will help, as I believe that was what my motherboard defaulted it to in the past. As for the page file size, could you be a bit more specific? How should it be set, or to what size, and how would that cause this problem? I'm curious.

Thanks for the suggestions though.

 

[Wamphryi]

It sounds like your PSU. It has to be eliminated from the problem. You could be risking other components by not doing so. Some BIOS will display the voltage readings in the PC Health section of the BIOS. If you see your voltage rising and dropping or coming in too low say 11 volt instead of 12 then your PSU is certainly suspect. Even if you cant see anything obvious there still get it tested as it may only be doing it every now and then.

 

[alltogethernow]

I followed your advice and went into BIOS to check the voltages. I'm going to take a wild stab in the dark here, but I'm guessing 10.97 volts on a 12 volt rail isn't good, is it? Especially if it's going up and down as well? Needless to say the computer's been turned off ever since. I'll be replacing that PSU ASAP then and see how it goes. It's good enough for me to indicate it's the PSU.

The weird thing is I've looked at the voltages before, but it either never clicked or didn't seem enough off, back when I was checking something else, to ever notice it. Thanks for pointing me that way.

Cheers!

 

[alltogethernow]

Best answer selected by alltogethernow.

 

[Mousemonkey]

This topic has been closed by Mousemonkey