Computer will not turn on.

Said this was the Windows Vista help/discussion forum, so here I go....
Specifications, if I can remember correctly are:
Nvidia 6100 nForce 405
2 GB DDR2 Dual Channel (ram)
AMD Anthlon 64 x2 Processor
400 GB harddrive
windows vista home premium
Model No.: T5426


I was turning my computer off one day and when it would not turn off, I held the power switch and it turned on and off real quick. Now when I turn it back on, it will turn off when it hits the Windows Vista loading screen, like right when it gets to it, it does not restart just shuts off and it is annoying. People are saying its the PSU which I doubt it because when I hit F2 or F10 to go to those menus when I first start my computer, the computer stays running perfectly until it try to boot it in safe mode or boot it normal mode.

This happened to me before when a friend messed my computer up and I found my old installation disk for vista and put it in and it worked perfectly, but now when I try to put the disk in, it shuts off when it tries to load up.

When all that happens, my computer will not even turn on when I hit the power switch, it only turns on after I unplug the computer, open the case, close the case, then plug it back in, but when I turn it off, it shuts off at the loading screen and then wont turn on again until I unplug it all again, this sucks.

I tried re-seating the CMOS battery or whatever its called, someone said it might work, but it did not. My computer does the same thing over and over.

Hay.. Have you got ur windows vista disk

Sounds like what happened to me when my PSU went out except that I didn't have to open up the door. It would shut off and then after that it might or might not turn back on. I had to keep trying as well as flip the power switch on the back of the PSU. Sometimes I had to discharge the power by hitting the power button after hitting the switch. If I got it going it might work again before shutting off. Once I had it going for almost 2 days before it shut off. Does this sound like you? Can you get it to boot at all? If you have the right tools and you know what you are doing you can test your power supply. If you have a desktop it should be relatively easy to replace it.