Beware the CMOS Battery

The computer saga continues.... after much sleuthing, and rearranging of hardware between my various frankenputers, I am 99% certain that my original problem began with a dying CMOS battery. The CMOS settings changed back to the factory default, which told the motherboard to use the built-in graphics card, instead of my nVidia 7900 GS. Thus, when I turned it on, no picture! (but it did boot, because it played the Ubuntu login sound). So the lesson is: When things go awry, especially with the video card, check your CMOS settings, make sure they stick, and keep some CR2032 coin-cells on hand!