[EDIT]hmmm.....whats going on at AMD? (and history of 3Dfx Rampage)

[SteelCrysis]

https://www.techpowerup.com/reviews/Inte...ce/26.html
A very interesting finding:

We initially planned to get this review done and over with just two GPUs, the high-end GeForce GTX 1080, and the performance-segment Radeon RX 480. When processing our results, we noticed an interesting trend that the RX 480 was posting bigger gains due to increased CPU speed than the GTX 1080. This phenomenon is more visible in the lower 1080p resolution, than in 1440p or 4K (where the RX 480 doesn't provide playable frame-rates in most games anyway). We initially dismissed this as behavior a performance-segment GPU designed for lower resolutions would exhibit. We then pulled out a GeForce GTX 1060 6 GB, a comparable graphics card from NVIDIA to the RX 480, and noticed that such gains were not noticeable.

From this we can conclude that the RX 480 has a slightly higher CPU overhead than the two NVIDIA cards. Graphics drivers need the CPU to crunch some serial processing loads at various stages of the graphics rendering pipeline, before they get fed to the GPU. Previously AMD's driver overhead was a vague assumption backed by very few benchmarks; this article is conclusive evidence, that the AMD graphics ecosystem definitely has more CPU overhead than the one from NVIDIA.