Strange hard freezes/reboots

[theterminator]

My PC had started acting weird in the last couple days.

Specs:

athlon 64 3000+ 2 ghz (s754)
2x 512 mb ram (corsair and samsung)
xfx nvidia 6800 xt 256 mb
2x seagate 80 gb hdd
msi k8n neo 2 plat nforce 3 mobo
audigy 2 zs
vantec van-400b 400w psu

I will be doing nothing special, eg. playing a game, surfing or idle and the pc will randomly hard freeze on me. I cant ctrl alt del, mouse mouse or anything, I have to manually reset. Sometimes it just turns off too.

I'm pretty sure it aint my 2 hard drives, I used chkdsk on em both and they both passed.

Ran memtest86 on RAM and it passed.

Havent made any recent hardware changes.

not an overheating issue as BIOS shows everything within spec.

It started happening in XP so I formatted to Vista and it still happens.

I think it may be a power supply issue and I was wondering if anyone knew of a way to test without and power supply to swap or a multi meter.

any suggestions?

 

[evongugg]

Install speedfan and check the voltages or go into the Bios.

 

[theterminator]

I went into teh BIOS and checked the voltages and them seem OK, but I admit I dont know what Im looking for there. Any advice?

 

[theterminator]

Ya, I checked those in the BIOS earlier today and they looked like they matched up, most were slight higher than what they listed as, eg 12v was 12.10 etc. So they are OK while in BIOS but I was wondering if perhaps they are getting drained once I boot into windows. I was wonder if there is a program to monitor these from windows.

Also, as a weird side note, whenever I start the system performance scan in Vista it triggers an almost immediate freeze/power down by the PC.

 

[theterminator]

any more suggestions?

 

[theterminator]

I hadn't tried it in safe mode but i assume its the same thing, doesn't seem like a software issue as the format changed nothing.

I removed and opened my power supply today and didn't see anything that jumped out at me as wrong, no leaking transistors etc. that i could tell.

I think I'm going to order a a new power supply on Friday.

Think this one should be good?

http://www.ncix.com/products/index.php?sku=18184&vpn=OCZ600GXSSLI&manufacture=OCZ%20Technology

 

[theterminator]

I'll post back and let everyone know how it goes.

Should be here Monday or Tuesday.