The curious case of the CPU Bottleneck: Results

Test Setup:
AMD Opteron 144 (1.8 Ghz, OCd to 1970 MHz), 1 MB cache.
2x512 MB DDR 400 Mhz RAM (Dual channel, OCd to 425 MHz)
MSI N9800GT 512 MB, Clocks: Core: 715, Shader: 1680, Memory: 800 (1600)

All benchmarks are at 1440x900, Maximum detail, 4x AA, 16x AF unless otherwise specified. Framerates reported are average FPS of actual game play.

Racing/Simulation games:

NFS-ProStreet: 12 fps
NFS-Undercover: 15 fps

In the NFS series of games, we see about 10 to 15 fps hit due to other cars and traffic. On a test track, while playing solo, we get around 25 to 50 fps. This means that the CPU bottleneck is truly noticeable in these games. The AI for the cars in the game seems to be quite intensive on the CPU. A dual core machine could easily turn the numbers in our favor.

Note that these games aren't all that graphically demanding. My earlier 6800GS gave around 7-10 fps at high detail on NFS Pro-Street.

Trackmania United: 30 fps

This is a slightly more stable case for our benchmarks. There are no AI drivers, and the game is highly playable at these frame rates.

Racedriver GRID: 20 fps

Another nice game for this test setup. At maximum detail, the game runs smoothly, even with AI players on the tracks. Also, IMO, the best looking racing game out on the PC, and very convincing handling too.

Tom Clancy's HAWX: 50-60 fps

A slightly unconventional game. Tried it on a friend's recommendation. Again, the game runs very nicely on this machine. Note that the game has an inbuilt benchmark mode thats a lot more intensive than the actual game. The first part of the bench runs at 60 fps and the second, insanely cluttered one runs at 15 fps. The average, as reported is 25 fps.