|
原帖由 Diamond.Ball 于 2008-8-7 09:57 AM 发表
拿N卡当物理加速卡
为什么不直接加一块物理加速卡?
因为在运算能力上PhysX PPU不如Geforce 模拟PPU:
评测中采用的GPU是9800GTX 对比的参照是AGEIA PPU
The initial group of tests here were completed on non-overclockedparts. The first test was performed without PhysX-acceleration, whilethe second relied on the PPU, and finally, the third utilized the GPU.The PhysX driver used is 8.06.12, which was just released this pastWednesday.
No PhysX Acceleration - 17.09 ops/s
With no acceleration, all of the work is left up to the CPU,resulting in somewhat lackluster results... at least as far as physicscalculations are concerned.
PPU PhysX Acceleration - 28.50 ops/s
Surprisingly, adding in the AGEIA PPU did little to to increase ourscore. The boost from 17.09 op/s to 28.50 op/s might seem impressive,until we take a look at the GPU results.
GPU PhysX Acceleration - 125.14 ops/s
Yes... here's the reason that some people are up in arms. This is arather substantial increase, but again, I still feel it's deserved. TheGPU is so efficient at processing physics calculations that it blowsaway even the dedicated PPU by more than quadrupling the averageresults. As you can see, that boost also effects the overall 3DMarkscore by a fair bit.
From a technical standpoint, the GPU was obviously much faster athandling the most popular physics processing that PhysX offers, so itmight very-well be that the PPU is actually a lot less capable than wefirst imagined.
I next wanted to see what sort of effect overclocking had on theresults, on both the CPU and GPU. Which overclock would increase thephysics more? With the PPU installed once again and the CPU (QX9650)overclocked to 3.6GHz, we saw a 9.3% increase in overall physicscapabilities.
PPU PhysX Acceleration (Overclocked CPU) - 30.53 ops/s
On to GPU acceleration. I overclocked both the CPU and GPU to seewhich one had the greater effect. The first result is for the CPUoverclock, still at 3.6GHz. The differences are once again just under10%, at 9.6%.
GPU PhysX Acceleration (Overclocked CPU) - 129.46 ops/s
Finally, putting the CPU back to stock speeds and overclocking theGPU (+21% Core MHz, +7.8% Shader MHz) pushed us up to 134.35 op/s...resulting in yet another 9.3% increase.
GPU PhysX Acceleration (Overclocked GPU) - 134.35 ops/s
The increases to be seen here will of course scale with the size ofthe overclock, and it's more of a coincidence that both the CPU and GPUoverclocks gave the same % increases. If the CPU was overclocked to4.0GHz or higher, even greater differences would be seen. |
|