Sadly, I need most of my bloatware and newest nVidia drivers.
So I did some not so scientific tests, WaltF4 accept my apologies.
with my set up...
tried setting fps cap to 120.
FRAPS and in game fps seem similar - one 'lags' behind the other (fraps updates more frequently).
DX7 offers no noticeable or slightly worse performance. (old machine did fine on DX7)
Turning texture detail to low offers poorer performance with shader quality set to low on both DX7 and DX9. That's a head scratcher.
I refuse to turn off bodies or ragdolls.
Usually (about 80 people on NA1) FPS ranges from 120-110, with some drops to as low as 85.
Join lag (start of round) stuttering is noticeable.
There are some wtf moments - such as people dying before I think I hit them.
Some maps are just hogs, and feel like playing at 15 FPS, even if displayed FPS is 105 or so.
Ultimately the experience convinced me that capping fps to 59 (my LCD's refresh rate) is likely the best option - 0 stuttering, and display stays constant 59.29/59.35