I have installed Windows 8.1 Update on a 5-year-old XP machine with an ATI Radeon X1550 graphics card. Everything works just fine except one 'minor' problem. When the computer is turned on, the screen remains blank until the first display power save event is fired by OS (currently set to three minutes). Then the display goes to the power save mode normally, and after that, the display wakes up and the screen becomes visible by moving the mouse.
The latest driver available for ATI Radeon X1550 has been installed.
Once visible, the screen also remains visible even if the computer is restarted -- but turning off the computer brings the problem back again.
Has anybody any clue about what might cause this kind of behavior?