When I turn on my computer it tries to start but the power lite goes off in the middle of start up and just sits there.
Could it be my power supply? Any ideas?

Thanks
Irene

has this just suddenly happened? have you added any extra hardware/ extra components? does the pc keep on even though the light is off?

it maybe a power supply problem, try looking at the link below for more help

http://www.fonerbooks.com/power.htm

yes this just started to happen. I install the windows - Security update for windows XP (KB890175). The computer stays on even though the harddrive lite goes out.

Sorry you have confused me. Does the pc actually boot up or not?

No the computer does not boot up - it tries to and freezes during the start up process.
It doesn't always freeze at the same place either.

Does your BIOS POST run thru?

Start tapping the F8 key after the POST to try to get into Safe Mode & do a System Restore to the point prior to the Windows Update.

can u see nething on the screen

I have seen heat issues cause similar problems. May be a stab in the dark, but check your CPU fan and make sure it is working properly.