I think my monitor is dying.
 

Has totally blacked out for 20 minute periods three times in the last month, along with occasionally getting way brighter (again for short periods but I can get it back to normal by hitting the brightness control). Now I've got faint horizontal lines running up the screen as if the Hz setting wasn't high enough.

Am I correct in worrying?

It's probably the monitor, but I had some weird stuff like that happen when a power supply was dying. I thought it was the monitor, especially since I bought a refurbished one, until the dvd drive wouldn't open. I replaced the power supply probably a year ago, and the monitor has worked perfectly since then.

Hmm. I do run 24/7. I'll check that this weekend.

Wow, I read that thread title wrong. Glad that said monitor.

Try the power supply thing.

does he look like this?

I read this wrong as well. Monitor is much better.