Just installed final catalyst 8.12 driver. Great improovement.
Q9450 - 2.66 Mhz, 4Gb RAM, Radeon 4850 1Gb VRAM, Vista 64 bit
GTA4 settings:
1280x1024
Texture: High
Render: High
Distance sliders: 55
Shadow density: 10
Everything else maxed out.
With 8.11 I get an average FPS of 31 (with the build in benchmark)
With 8.12 the average gets to 41 FPS wich is about 30% better
Can't wait for the official Rockstar patch for the game
looks like my 2900 just won't cut it anymore.