Benchmark Results: vReveal On The FX-8150 And Radeon HD 7970
Using the same platform, we swap out the old Radeon HD 5870 in favor of the newer Radeon HD 7970 to gauge whether or not the GCN architecture has any bearing on our benchmark results.
When working with only one render effect, an admittedly lightweight metric, there isn't much difference. Even at 1080p, the Radeon HD 7970 leaves our FX processor at 12% utilization, whereas the Radeon HD 5870 dropped the FX's workload to 10%. That's right. Our data shows a slightly higher CPU load with the newer GPU.
Because this result reverses as we apply more effects, it's conceivable that the 7970's compute resources aren't being utilized as effectively under the light load. Meanwhile, the heavier burden lets the 7970's 2048 shaders stretch a bit. More important is that we’re still seeing low single-digit utilization with accelerated 480p video and a 4x performance gain with 1080p.
Understandably, there is no visible difference in render speed when switching up to the Radeon HD 7970 here. The test only goes up to 100%, and trading GPUs should have no impact on software-only processing.
Again, in terms of CPU utilization, we’re seeing almost no benefit from the Radeon HD 7970 under our heaviest vReveal load compared to the older Radeon HD 5870, despite the 7970's architectural advantages. This is still good information, though. It tells us that we can't always expect scaling that corresponds to the GPU's potency. Of course, this is going to vary by application and, in some tests, a faster graphics processor absolutely will mean better performance.
Apart from an almost imperceptible and insignificant nudge of the needle in the 480p software test, these results show the same 100% rendering seen with the Radeon HD 5870.