I was working on my computer when the monitor suddenly went black. Nothing seemed to be different in the tower; there were no sound changes, no light changes. The monitor's power light stayed on. I recently acquired another computer and monitor from a friend and decided to hook both monitors to both towers to troubleshoot. Both monitors work fine when hooked up to the second computer, and both monitors stay blank when connected to the first computer. So, the problem has to be in the tower. What sort of problem does it sound like I have? What should my next step be? The only spec I have for the machine, since I can't access the hard drive, is that it's running XP.
you could have a defective video card.if it is a built in video card,then you have problem there.But see first if your motherboard have a video card slot like agp or pci express.then you have to borrow the right video card to test it.
If your screen resolution is set higher than the monitor can display (too high resolution or refresh for LCD or CRT) and PNP is not setting the correct max resolution, you could be stuck in a display mode the monitor cannot display because it's beyond spec. Try plugging the questionable card into a monitor capable of very high resolution....also try the output of other connectors on the card (ie, DVI vs dsub or TV out) to see if indeed the card is bad....simply beginning the installation of a windows xp cd will display lowest VGA resolution on whatever monitor and show wether or not the card is good. Cards do die sometimes.