Well, perhaps not the Problem of you all, but i noticed a strange behavour with LFS, too.
When i switch on AA, LFS will just get unplayable in Window-Mode.
The Screen fills from top down just line for line, the higher i set AA the slower it goes.
But as soon as i switch to fullscreen, it runs ok.
Without AA everything runs well, in Fullscreen- as well as in Window-Mode.
I got this behavour after i reinstalled Windows some Month ago. No Hardware changed, just reinstalled Windows. Before that i could run LFS with 8xAA in Window-Mode, now its not playable.
Thats no big deal for me because i allways Race in Fullscreen, but sometimes you just want to check IRC or something between Races and hit F4 ...
Its so funny because i just installed all drivers as i used before, but it behaves different
Oh well, my Hardware: Athlon64 3200+, 1GB Ram, Radeon9800Pro
but because it run well with same Hardware before Windows-Reinstallation I dont think its something with that (As well as the Fact that without AA everything runs fine, too.)
Oh yes, with AA the CPU is 99% used by LFS in Window-Mode, but only 40-70% in Fullscreen or Window-Mode without AA.
Perhaps someone knows this Problem?