[ut2004] ut2004 stuttering

[kristjan]

I've modernized my system and tried to run ut2004 on it with latest 3369.2  
patch on linux.
No matter what quality settings I use, the game stutters on some maps.

For e.g. BR-Anubis - I think this is the worst (I only play bombing run  
online curently).
First when I spawn in small room, when heading to larger open area the  
game will stutter for a second
and then the stutter will happen again when heading to new areas of map.
Stuttering seems to calm down and stop when I explore full map.

I know it used to work very well on linux, but I haven't played it in  
quite some years.

I've tweaked ini settings, but that didn't help at all:
bShouldPreload=True
bDesireSkinPreload=True
...
UsePrecache=True
...
UsePrecaching=True
VARSize=128
ReduceMouseLag=False

I've tried to run the game from bare X with xterm only.

System specs:
- athlon 640 (quad core)
- 4GB ram
- gefroce GTS 450 (1GB gddr5)

It works very smooth under windows with maximum settings and no ini  
tweaking.
What could be the problem?

-- 
kriko