Computer hardware help needed again!!

[Solecord]

Ok so yesterday I was on my PC and then left the room to watch tv, leaving the PC on. About 2 hours later I went back by the PC and it was off. There were no power surges in the house so it seemed weird. I powered back on, got some POST errors, got it to reboot, and then started playing around on it. After a few minutes it shut off again. I left it and went to sleep. Today I turned it on and about 2 hours after turning it on I got a BSOD saying something about a possible hardware issue. I rebooted and got a POST error. Eventually went into BIOS, checked the voltage monitor and one of the numbers was highlighted in red - it showed the 12V rail to be running between 9.6-9.8V. That seems kinda low!?! I then exited BIOS and went to load the OS and it immediately shut off.

Is the BIOS voltage monitor usually accurate or could that have just been a fluke? If the PSU starts to go, is random shutdowns a common symptom?

If I need to replace the PSU, any recommendations on one to get? My hardware specs and current PSU are below. If it's not a PSU, any other ideas as to what might be going on?

Intel Core 2 Duo Processor E6750 at 2.67GHz, 1333MHz FSB, 4M Cache

Vigor MonsoonTM II TEC Active CPU Cooling System with LCD Display and Triple 120MM Case Fan

Tagan TG1100-U96 TurboJet nVidia-SLI Certified 1100Watt Power Supply

Asus P5N32-E-SLI NVIDIA nForce 680i SLI 16 X 2 Intel Quad Core Ready

2GB Corsair TWIN2X2048-8500C5D DDR2 1066MHz Memory (2 X 1024MB)

320GB S-ATA II 7200 RPM Hard Drive

320GB S-ATA II 7200 RPM Hard Drive

500GB S-ATA II 7200 RPM Hard Drive

nVidia GeForce 8800 GTX 768MB Xtreme Edition @600MHz, DVI and TV Out

NEC Internal AD7170A 18X Dual Layer DVD+/- RW + CDRW Rewritable Drive

Creative Sound Blaster X-Fi Xtreme Gamer Retail Edition

Onboard Gigabit (10/100/1000Mbps) PCI Network Card

PCI WiFi Wireless 802.11b/g Wireless Card

Running Windows XP SP2

[Mindf!3ldzX]

I've been ordering these as replacements
Newegg.com - Sunbeam PSU-BKS-480-US 480W ATX12V Power Supply - Power Supplies

So far I have replaced 3 psu's with them and they have worked flawlessly so far,I'll be ordering a 4th here after awhile to get the other dual core box back up and running.

[=peg=]

that is most likely the PSU failing.. better replace it before it blows and breaks other hardware along the line..

[Polarite]

Yea Solecord , it started here too like that...
Then one day I heard a big bang and the pc was dead (the psu).
I was lucky nothing else was broken.

Better replace it before other things are damaged too.

[foq]

Voltage monitoring is usually off, but to be off from 12 to 9.6-9.8 is pretty bad. I'd get a replacement power supply. I don't think Mindz's suggestion would work very well as TEC coolers take a lot of power to run. Power supplies are the most critical part of the system, so you have to ensure quality, because if the power supply goes bang, chances are a lot of other stuff will too. This is my favorite power supply ever. 1000w (don't worry about it being 100w less than your TaGONE, I assure you it is in fact much more powerful), SINGLE, immensely powerful +12v rail (splitting the +12 rail can cause problems because one rail can become overstressed while the other rail is just chillaxin), and a 100% modular design. Expensive but you should never need another power supply again.

Newegg.com - SILVERSTONE DA1000 1000W ATX 12V 2.2 & EPS 12V SLI Ready CrossFire Ready Modular Active PFC Power Supply - Power Supplies