Need Urgent Help!

[lally07]

I didnt know whereto post this because im not sure what the problem is. But. I just installed a new copy of Windows 7, and when i was installing drivers etc. My computer just shut off. No warning, no nothing!. Now i have had experiance of it doing the same thing before, but tht was only when playing very high graphical games. And certainly not when just browsing the desktop. Then it got worse. I switch it on and it bareley gets to the startup options screen (Safe Mode, Start Windows Normally etc) and normally shuts off when on the motherboard logo screen! I have got it into my head that it is my PSU giving way. But i need a second opinion and things to try?
Thanks.

 

[StrangleHold]

Since you said it had shut down before, it could be the power supply. But it could be a Choke or Cap going out on the board. What brand power supply is it? Look around on the board and see if any caps look like they are bulging on top. If not, know anybody that has a power supply you could test it with.