MacPro 5,1 Sierra 10.12.6, Radeon 5770s and 7950 FCPX, BruceX, Compressor, AME Speed Comparison

II just swapped the CPU from a quad core 3.2GHz to six core 3.46GHz on my MacPro 5,1 main machine. I will soon install macOs High Sierra and FCPX 10.4, but need to run some test first.

Also I'm looking towards buying a Radeon RX580 in the near future (when the prices are down), but in the meantime I still rely on my trustworthy Radeon 7950 Mac edition.

Also just for kicks I installed two Apple Radeon 5770s to run some processing comparisons, see results below.

A) The machine is a MacPro 5,1 mid 2012, Quad Core 3.2GHz, 16GB RAM running macOS Sierra 10.12.6. No other app than FCPX is opened, saving to the internal system SSD.

FCPX BruceX, Share ProRes4444QX
One 7950: 53sec.
Two 5770s: 45sec.

Compressor BruceX ProRes4444QX file to Youtube "Up to 4K" h264 Preset
One 7950: 75sec.
Two 5770s: 61sec.

Adobe Media Encoder BruceX ProRes4444QX file to Youtube 4K h264 Preset (GPU acceleration OpenCL)
One 7950: 13sec.
Two 5770s: 29sec.

B) The machine is a MacPro 5,1 mid 2012, Six Core 3.46GHz, 16GB RAM running macOS Sierra 10.12.6. No other app than FCPX is opened, saving to the internal system SSD.

FCPX BruceX, Share ProRes4444QX
One 7950: 53sec. (Same speed as quad core! That wasn't expected.)
Two 5770s: ??sec.

Compressor BruceX ProRes4444QX file to Youtube "Up to 4K" h264 Preset
One 7950: 42sec. (Faster than quad core, as expected.)
Two 5770s: ??sec.

Adobe Media Encoder BruceX ProRes4444QX file to Youtube 4K h264 Preset (GPU acceleration OpenCL)
One 7950: 9sec. (Faster than quad core as expected.)
Two 5770s: ??sec.