a technical question for the hivemind

[eliade]

At home, either my monitor or my video card is crapping out. The symptoms and conditions are:

Usually when I start up, it works fine at first. If I stay on and the computer's in constant use, it continues to work.

If I leave it long enough that the screen saver kicks in, I can't get the picture back. (I've got screen saver set to kick in after 90 minutes, maybe two hours right now, but that's not ideal.)

At that point, if I turn the monitor on and off, I'll get a half-second of image before it fades.

If I turn off the computer and restart immediately, I get the initial Windows logo, and the cursor shows up briefly, but the screen remains black when it's fully up.

If I wait several hours, I can usually get it to start fine again--but the time frame is inconsistent.

Any thoughts? I can take it into a shop for diagnosis, but if it's something I can just replace myself--either the card or the monitor--that'd be easier.