Well, first off here are the specs you need to know:
Sapphire 9800Pro 128MB 256bit still in guarentee
ATI Catalyst 4.8s, had the same problem with 4.9s though
DirectX 9.0c
WindowsXP Pro SP2
here's an example of my problem:
I have installed 4.8s instead of 4.9s (I think it was after i installed 4.9s that it went funny) and reinstalled DirectX
Any Ideas?