I am having a problem with playback in CS3

I upgraded my os from xp64 ti vista 64 I have Installed cineform prospect 4k Build 3.4.8.191 15-January-2009 now I am having problem with playback, display resolution is low after i palyback the timeline.

I have did same thing in two different machine

one is use ATI radeon 1900 x and other one have GEFORCE 9600GT

Why it play back in low resolution even I my play back setting in highquality option