You need to determine if the power supply is coming on. The keyboard flash is evidence that it tried but maybe powered down. You should hear fans running. If not, the power supply started and powered off. It will do this in response to an overload or underload. A fan that "twitches" and stops is an indicator that this is happening. If you can determine the PS powers on and then off, you will need to see if something in the system is overloading it or whether the PS itself has become defective. This is best done by disconnecting unnecessary devices such as drives, add in cards except the display card, etc. and trying to boot the machine to at least bring up the POST screens. You need to rule things out one at a time this way. Repost any findings. Good luck.
a friend of mine decided to leave her computer on...but thought it would be a good idea to turn off her monitor...the next morning when she turned on the monitor...the screen showed her desktop but her mouse was froze up...I told her to re-boot..turn the power off waite 20-30 seconds and then turn the power on...nothing...now I have this Compaq junk at my house trying to figure out whats goin on. I tried anothe video card..same thing no video no beep.. the only thing that happens is the keyboard light fash for a second, that's it. Any direction would help...Thanks

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