That really looks like its running in software mode - i.e. no hardware acceleration.
There is an nvidia utility somewhere which you can use to tell you what settings your card is running with - cant remember what it is and the machine I'm on at the moment doesnt have an nvidia card in it. Try searching the forums I'm sure I found it in there somewhere.
I've had problems before and found that completely uninstalling the graphics driver and reverting back to a 'normal' setup i.e. software mode, doing a full reboot and then running through the install process again can solve a few things. Make sure you uninstall the MesaGL(??) driver but not the MesaGL library (search the forums) as that can **** things up as well - I've seen linux default to running the software MesaGL driver instead of the nv driver when both are installed.
The machine I'm on at the mo, 1Ghz, ATI Rage 128 and software mode gets around 270fps.