Mountain House (CA) - Nvidia’s released two powerful weapons with its GeForce 9800 GTX+ graphics card: The company can now compete against AMD’s brilliant Radeon 4850 graphics card on price and the company finally has an answer to ATI’s dominance in 3DMark benchmarks. You can bet the farm on Nvidia claiming the highest scores in the physics discipline.
We were able to get a first impression of the PhysX performance of Nvidia’s latest cards by using the company’s ForceWare Rel177.39 drivers and an executable file named PhysX 8.06.12.exe. We found that the new ForceWare driver has serious installation problems and the software felt a bit rushed to us although since our initial tests, Nvidia has corrected the problems.
Aside from that hiccup, Nvidia appears to have a jewel on its hands. The results we saw in the CPU Test 2 - Crash’n’Burn Physics discipline were impressive. So, how much more physics horsepower does the GPU deliver in physics than the CPU?
Our Intel Core 2 Extreme QX9650 clocked at 3802 MHz delivered a CPU score of 15,005, which jumped to 42,436 using a single GTX 280 card. With two GTX 280 boards, we got 42,374 CPU marks, and three GTX 280 boards resulted in a CPU score of 41,387.
The decreasing score of the 2-way and 3-way SLI configurations are not surprising, as PhysX uses only one GPU and currently isn’t multi-GPU scalable. So, the lower score should be expected, especially since the SLI bridge is taking its toll: CPU cycles are consumed because of the synchronization between two or three cards. Additionally, there is an increased saturation of PCI Express bus.
It is interesting to note the overall 3DMark score. Compared to the preceding driver, the GTX 280 performance index jumped by 2000 3DMarks (17%) for a single-card configuration. With two cards, the performance index jumped by a massive 5343 3DMarks. This is an astonishing 25% increase from one driver version to the other.
However, Triple-SLI showed that even our 3.8 GHz CPU limited the capability of the GPUa - since one CPU apparently cannot feed all three GPUs. We witnessed a performance increase of only 17% compared to CPU-only physics.
Nvidia’s new PhysX driver delivers a higher score only in Performance mode, while the Extreme mode is predominately GPU bound, which means that the impact of a faster CPU is limited.
Nvidia promised that it will deliver PhysX API compatible with all GeForce 8 and 9 cards in July. For now, PhysX only works on the GeForce models GTX 260, 280, 9800GT, 9800GTX, 9800GTX+ and 9800GX2.
