Nah... the same problem occured in Halo PC/CE.
The engine locks gamespeed in with the framerate. Halo PC/CE fixed this by allowing a 30FPS lock mode.
Mentioned
it to the PR people for Halo 2 Vista within a week of its release and
they said they'd include it in the patch... unfortunately Microsoft
pulled the plug before that.
Your problem is not that your computer is *too slow*... it's that it is *too fast* and the gamespeed is getting confused is to how long a game-second is (which appears as juttering).
You
can sooth this issue by playing with your vSync, I did it in my
driver... but since there'll be no patch for Halo 2 Vista (and no I
don't count 'asserror' removal as a patch) there will be no 30FPS lock.
The problem lays in that Halo 2 is a console game and Bungie designed the engine to be locked at ~30FPS for TVs.
If you ran FRAPs or something you'd notice you probably would be getting pretty high framerates... 80-100+... but it isn't a stable high framerate.
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