http://gearsforums.epicgames.com/showthread.php?t=620375&highlight=hangs&page=3
I am not the only one have look at the link.
The Unreal Engine 2 stutter problems (relating to 8800 cards and XP) have been COMPLETELY fixed - even Unreal 2 is silky smooth. You are using the 177.83 version, right - not some other 177?
it must have been about a year now?