WIERD Problem, will not boot.

Okay, two nights ago I turned off my computer, (I usually just leave it on) before I went to bed. The next afternoon, when I went to turn it on, it would not boot, and did not even get to the post-beep stage. The hard drive light on the front of my case seems top be working fine, but the power light is really dim, and seems to brighten when I hit the reset button. On a whim, i unplugged my USB drawing tablet, which seemed to make the power light a little brighter as well. Also, when I power it on, it appears to be checking through the drives like it normally does, as both of my CD drives blink several times. Finally, The keyboard does not show its regular 'num lock', 'caps lock' indicators when the computer is powered on, but they turn on as soon as I use the front power button to shut down my computer.

My motherboard is an Asrock socket A,
Processor is an Athlon XP 2800+
I'm running 2 CD burners, 1 HD, a wireless card, and a surroundsound card.

Any ideas whats broken, or how I can fix it?

 

I kind of suspected that, but didn't really know how to test. I dont remember the size of the PS, as I'm on a library computer and can't check it, but I think its about 400 Watts, and probably a solid 5 years old.

 

This article may help narrow down the problem (component).

http://www.d-a-l.com/articles/library/34.html

 

I tried starting it with only the hard drive in (I took out my wireless and sound cards, a stick of RAM, both of my CD drives and my floppy drive) and it still wont do anything. Is the really dim power button a pretty good indicator of power supply failure? I don't have a lot of money to take it to a shop or buy stuff to test it with, and it was running without a hitch before I shut it down. Anyway, I will try it with nothing on it but RAM, and see if I can get it to POST. Thanks for the help.

Edit: My CPU fan seems to be running at full speed, if that means anything.

 

Fans require little power. If you have a close friend willing to let you use their (compatable) power supply to swap out yours for troubleshooting that will eliminate the PSU possibility.