Ubuntu 12.04 on PC with ATI card using built-in drivers. Gnome classic (no effects)
A dual monitor setup works perfectly for admin user A, with both screens showing at 1280 x 1024.
New admin user B created, also set to Gnome classic (no effects), when logging in the monitors are mirrored by default. Looks OK.
Using System Tools / System Settings / Displays, change settings to be exactly as user A, not mirrored, 1280 x 1024. Apply and screen is garbled, even though settings for user A & B are absolutely identical. If I drop the resolution down for user B, I can get a result.
I've tried copying and manipulating the ~/.config/monitors.conf but no good results for 1280 x 1024.