ok, ive got the craziest speed tip. im getting a constant 80fps in the indoor deathmatch level, and a constant 60 fps in the outdoor one. i saw this on the ina forums, ill give a link as well.
basically go to ur ut2003.ini in the system folder of ur UT2003 directory. press ctrl-F and search for 'mouselag' (without the speech marks). now edit the line which says 'reducemouselag=true' to say 'reducemouselag=false'.
this sounds stupid, and i didnt believe it, but it seriously does boost fps.
heres the thread on the ina forums :
btw, just read on that thread that the benchmark.exe uses a different .ini so u wont see fps boosts using the utility, unless i guess u modify that .ini, but i havnt tried that yet.