As I get closer and closer to actual activity my screen will turn (sky) blue. No plane, no ground, no con, no nothing. Just a blank blue screen. After a couple seconds it will blink back to show all the elements it's supposed to show, then go blue again. It seems to get worse the closer I am to "activity", such as other aircraft, enemy fields...basically anything I need to see.
Oddly enough the switch from b40 to b41 uses a bit more than twice the video memory for me, too.
Aircraft: F4U-1
System:
P4 2.6
1.5G RAM
nVidia GeForce4 ti 4600 vid card
128.3M video memory available
128.1M video memory used