Weird computer shutdowns - never seen this happen before

Nebel

Distinguished
Aug 20, 2008
8
1
18,515
Hello.
About 1 and a half month ago, my 8800GT burned. It was extremely hot when I took it out, I could only hold it in my hands for 10 seconds or so. I figured, a cable might've been stuck in the fan and the card got too hot. So I sent it back for repair, and used my old 6800 ultra. However, about a week ago, I started getting weird computer shutdowns, not only while playing games, but even while surfing, listening to music, watching a movie.
Everything in my computer is overclocked, so overheating might've been the problem. Yeah, until I checked my temperature. CPU never went over 55 celsius on load.
I thought, what the heck, maybe it's just my old video card not being able to cope with newer hardware, and decided to wait until I get my 8800GT.
I got it today, installed it, started playing, and after about an hour, BOOM! Shutdown! I was so angry that I smashed the computer and almost choked on the dust :)
Anyway,
Things that happen after the shutdown:
1. Sometimes starts normally.
2. Sometimes seem to start normally, it lights up the motherboard, but both cpu and video card fans are not working, and there's nothing on the screen.
3. It starts the cpu/video card fan for few seconds, then powers them down, then up again for few seconds, then powers down, and so on.

I noticed one thing however. The 12V seem to vary alot. From 11.8 to 12.05. Sometimes, when it refuses to start, I try to push the big power connector (the fat one coming from the PSU), or move it a bit, and then it would power up normally.
I am almost certain that my PSU is dying, but I'd like to get a second opinion on this. The integrated network card in my motherboard have suddenly stopped working, and that's what makes me not being 100% sure it's my PSU messing around.

While I had my old 8800GT, my cpu was able to work on 2.8ghz, now I have to go as low as 2.5ghz (the original being E2140). My motherboard is Gigabyte P35-E.

Both my cpu and motherboard are only few months old, while my PSU have been serving me for over 4 years. It's called Antec TruePower 430W, and it worked perfectly until now (even with overclocked E2140 and 8800GT).

Any advice is appreciated.
 

Mondoman

Splendid
My guess is that the TruePower 430w, w/+12V rated at 26A, wasn't really powerful enough for a high-power system like yours. Overloading a PS can certainly make it start to go bad. Another possibility is that you're overheating the PWM (MB power circuitry) or north bridge; both heat up even more during overclocking.
 

IH8U

Distinguished
Dec 29, 2007
1,612
0
19,860
Dust can also cause a massive temp change (especially if it has built up in the card, HSF, and PSU) First replace the PSU, then clean the computer (canned air is effective and should be done monthly)(more often if you are in a dusty environment).