Have you updated the video driver from the Compaq website? It could be there is a new driver that takes care of this problem.
I have a problem with my laptop that the screen freezes and i can't close it except by pressing the on/off button for a long time. And sometimes it appears a blue screen with many letters and numbers and at the buttom "Phyisical error" and it restarts by itself then freezes. When i open it again after a while it says "Computer restarted after an unexpected shutdown. WinXP detected a possible device failure. The driver for the display device was unable to complete a drawing operation" and says that ATI Mobility 128 AGP 2X (COMPAC) could be responsible. I don't think it is a software problem cause the screen freezed with me when i was formating the laptop and when i was installing WinXP. By the way, i bought the laptop years before and it is Compac Presario. What shall i do? SORRY for the long post. Thanks in advance.