First, I'm computer illiterate.
I searched the forums and couldn't find a similar problem.
OK, last night I did the upgrade from 10.04 to 10.10. When it restarted, the monitor went into power save mode and I couldn't wake it up.
1. Shutting down the power. That is the only way I can restart it. When it restarts it goes through the usual steps up to the "Ubuntu 10.10" splash page, then goes into power save mode.
2. Hooking up another monitor. Same problem.
3. Restoring all the BIOS to defaults. Same problem.
4. Booting from my old 9.04 disk. I was SURE that would work, but the same thing happened.