System lockup at the beginning of each new level only if gl ext enabled

[csilver]

JK II is working fine most of the time. However, consistently, every time I enter a new level (only if gl extensions are enabled, I realized) the system freezes hard: The monitor seems to lose its connection with the OS, and the screen goes blank, while loud static emanates from the speakers. If I reboot, the system returns to normal.

 

This problem does not occur when I start a new game, but does occurr at the end of each level that I've finished so far (levels 1 and 2): The level status screen appears - and the new level begins to load - but when the progress bar completes, the problem occurs.

 

However, if I turn off gl extensions and enter a new level, the level loads fine. Interestingly, if I move around a little, at this point, and then turn gl extensions back on, the systems remains stable until the end of the level.

 

My system is:

 

Athlon 650

Windows XP

Radeon 8500 retail with latest drivers (6.13.10.6037)

 

Considering the circumstances under which the problem occurs and the harshness of the symptoms, this is one of the wierdest problems I've seen in a while. I've never seen anything like this is in another game. Anybody have any ideas? BTW, what does turning on/off gl extensions actually do, anyway?