The bottleneck come from your integrated video card. The nexuiz engine wasn't really optimized for the bottom of the range system because the developers has not the same resources than a gaming studio, even a small one. They do it on their free time, and don't get help from any gpu company for example.
Another reason is the main engine developer mostly had top of the range nvidia gpus until recently, so the engine performance wont be optimal on an ati platform.
Anyway some tips to get the game playable :
- press the low quality effect button in the menu and a use small resolution like 800x600
- to fell less the fps drops, use a constant framerate with
cl_maxfps 60 in the console (shift+esc to open it)
- set gibs to none in Multiplayer / Player Setup
Now you will need to make a timedemo of demo3 in the menu to determine what run better on your current system between having :
- 'Vertex Buffer Objects (VBOs)" set to Vertices or Off.
- "use OpenGl 2.0 Shaders (GLSL)" enabled or not.
Both are in Video tab (settings menu). Please provide feedback even if you don't play the game, info could be useful.
