Originally posted by mixedupmacandpc
Interesting one dale! My first thought was GPU conflict, as CS4 is now using that instead of your cpu for graphical display. Have u checked ur GPU specs against the ones posted as requirements at Adobe? What machine/config are u using?
But here are two things to try:
1) under preferences/performance/GPU settings, start to untick checkboxes and test to see if any of those settings when disabled help.
2) reset all ur preferences by following the adobe procedure for ur OS.
Well, good luck!