After playing for about 5 minutes the screen starts to "shiver" best way i can describe it is that its as if ever row of pixels shakes slightly from side to side in a small wave.
Understandly this tend to make me feel ill and makes reading impossible - any ideas as to whats causing it and how i stop it?
I can't screen shot it as if i do - the screen shot comes out normal looking .
The graphics card is ati, with some old 8.*** drivers, OS vista
thanks