What does "looks like its broken" look like?
Are you able to take a photograph and post via imgur?
That said, "sight unseen"....
Probably some loose connection or component.
Warms up, expands, the connection tightens.
Try re-seating all PC cards, cables, connectors, etc..
Culprit could be in the monitor as well - you will probably need to leave the monitor alone.,
No harm in reinstalling video drivers - just as a matter of elimination.