It could just be an engine thing. SoF runs on a heavily modified q2 engine with the Ghoul engine created by Ravensoft slapped on top. The update probably just does something to affect its performance on anything from chipset to vid card.

Kinda like running test drive 3 on Pentium. :)

As for unreal, It runs flawlessly on my machine. Every Unreal/UT wngine game runs flawlessly does for that matter.

anyhoo, EAX in both these games really isnt worth the hassle dude. Id just stick with stock installs.