I don't remember seeing this issue, but the last time I played through Unreal 2 was in 2009 on a GTX 280. It's interesting that the loading times increase. I always felt like that game had pretty long load times, even compared to other games with the same engine.
I used to get problems on Athlon 64 era processors in Unreal and Deus Ex, where the game would randomly run at either half or double speed unless I forced it to one core, but have never seen that issue on newer Intel processors.
I play UT and other Unreal engine games at 120fps and they seem fine. Although I've had it that way for so long that I may have just gotten used to whatever the problems are.