It's multi-boot, with Ubuntu and XP on the native IDE channel. Those 2 display fine.
The other 2 OS's, PCLOS and FC8 are on another disk, which is on a PCI/IDE controller card. If I boot either one of them, the display is off-center to the right, by the same amount - about 3/8".
Since both are off equally, it has to be a BIOS setting - right? And not a X.conf setting?

