Random PC Restarts

[destruct85]

Just lately my computer has started randomly rebooting itself. No real changes to the hardware, it just started out of the blue. The nature of the restarts is what gets me though. When I first turn it on I'll get a good 6 or 7 hours out of it before it restarts. After it restarts I'll get probably an hour before another restart. Then after that maybe 15 minutes before the next. This continues until it simply starts then restarts immediately. If I leave the PC off for a while I can get longer out of it again. The longer I leave it off, the longer I get out of it (to the limit of say 6 to 7 hours). I'm not getting a BSOD even with Automatic Restarts turned off.

The computer is currently about 5 months old and I've never had problems with it before this one. The current specs are as follows:

Intel Core 2 Duo E6600
Gigabyte GA-965P-DS3 (Rev 3.3)
Sparkle Power Action 600 (PSU)
2x1GB OCZP10002GK (Running in dual channel)
XFX 8800 GTS
SATA Western Digital 250GB Hard Drive

Aside from the timing I mentioned above there is nothing else unique to the restarts. It isn't in specific apps or anything considering sometimes I don't even get into Windows before it crashes. So far, to fix the problem, I have tried:

-Updating BIOS to newest version
-Swapping hard drives to eliminate software/corruption problems
-Running computer with no video card
-Running each stick of ram individually
-Running RAM through memtest86 on a fresh boot. Successfully got through a full pass of all tests
-Clearing CMOS and also replacing CMOS battery

You'll probably notice two glaring things missing from that list. First is overheating. I'm pretty confident it isn't overheating. Most times when it crashes, the video card is running around 60C and the CPU cores at 40-45C each. To make sure of this though I ran the PC with the case open and a room fan pointing at the case. I then witnessed it crash with both cores just below 40C and the video card at about 50C. I'm pretty confident these are well within acceptable ranges for these components.

The other things I have yet to test are the motherboard/PSU/CPU. This is where I am hoping for some help. I'm at the point where I'm going to need to test these things and curious which of them you think it is most likely to be (since I am going to need to purchase the parts to test them). Hell, if you have other suggestions for what it might be, I am of course entirely open to those as well.

Thanks for your help

 

[Tmagic650]

Try swapping out the power supply

 

[link590o]

I'm with Tmagic on that one. Sparkle isn't a big name brand. nor do i recall them being on an unofficial PSU rank list i found. it may be 600 watts, but i don't think it's high enough quality or efficiency.

i'm fairly confident that this power supply is more than capable of running that machine, and leave some headroom. it's only 50 watts below your current power supply:

http://www.newegg.com/Product/Product.aspx?Item=N82E16817103941&Tpk=Antec+Neo+HE+550W

it's 99.99. fairly cheap for such an excellent power supply. according to the list, it's tier 1 or 2. as compared to tier 3 or NOT recommended.

if that doesn't fix the problem, then you'll have to go with higher power, and more expense. but i'm very confident it will power that system.

i highly doubt that the motherboard or the CPU could be causing the random restarts. unless the motherboard isn't regulating the voltages properly. i find that doubtful because gigabyte is a decent brand. and that's a very nice motherboard model.

you can check the power supply rankings here:
https://www.techspot.com/vb/topic92076.html

 

[destruct85]

Thanks for the input. I was leaning towards PSU myself to be honest for the same reasons you described link. I'm gonna have to pick up a new PSU to test it out. One you linked seems like a good possible choice, but being in Canada, Newegg isn't possible so I'll have to see what prices are like up here. Either way thanks for the help link and Tmagic. Hopefully a new PSU does the trick