If it's a VGA monitor you probably need to hit the auto-adjust button on it. Different graphics cards and drivers produce slightly different timings for the same mode, so the monitor has to compensate, and it only adjusts its setting when you first get it or explicitly tell it to.
Thanks! I don't know about my relative's monitor, but the monitor attached to the T42 has a dedicated "Auto" button. I think I had waded through the separate menu choices without success, but I never tried that "Auto" button.
Pressing "Auto", the image futzed around for a few seconds and then apparently aligned properly. It didn't even mess up my brightness setting.
Sigh... I'm getting old.
I guess I'll add that for a long time, this monitor was dual boot, and I wasn't too interested at regaining the pixels in Ubuntu, only to lose them or their corresponding columns on the other side, under Windows. Nowadays, no longer a concern...
