Have you check RED Helium Playback with the Radeon?
RED Camera Sample R3D Files
www.red.com
I downloaded the 3 Helium 8K S35 24fps clips. City/Moon shot Redcode 8:1 is #1, Animal shot Redcode 7:1 is #2, City traffic shot Redcode 7:1 is #3. Resolve 15.3.1, 8K timeline, image scaling/output scaling set to HD for playback. Camera Raw settings set to Camera Metadata.
Playback with Full Res Debayer, with or without basic correction:
#1 12.5 fps
#2 10.5 fps
#3 10 fps
Playback with Half Res Premium Debayer, with or without basic correction:
#1 12.5fps
#2 10.5fps
#3 10fps
Yes, Full Res and Half Res Premium were the same. I even went back and ran both again.
Playback with Half Res Good Debayer, with or without basic correction:
#1 19 fps
#2 15 fps
#3 14.5 fps
Playback with Quarter Res Debayer, with or without basic correction:
#1 23.976 fps
#2 23.976 fps
#3 23.976 fps
Playback with Full Res Debayer, with basic correction & TNR:
#1 6.5 fps
#2 6.5 fps
#3 6.5 fps
Playback with Half Res Premium Debayer, with basic correction & TNR:
#1 7.5 fps
#2 7.5 fps
#3 7.5 fps
Playback with Half Res Good Debayer, with basic correction & TNR:
#1 8 fps
#2 8 fps
#3 8 fps
Playback with Quarter Res Debayer, with basic correction & TNR:
#1 11 fps
#2 11 fps
#3 11 fps
With the TNR on I did hear the GPU fans get louder than I ever heard the 1080TI. Kind of a whining sound because of the blower type of cooler. Typically I would leave the TNR off if possible while doing any actual grading (adding the TNR at the end) so the noise wouldn't bother me anyway since that would be something I leave on only for final rendering. That is unless a shot is really noisy, but then to get the realtime playback you have to render cache anyway, in which case playback with render cache wouldn't tax the GPU as much. Either way, I don't see the noise being a huge issue. If a model of Radeon VII comes out with a different cooling system that isn't as noisy then maybe I would upgrade, but I don't see it as a big deal right now.
Quarter Res Debayer looked great on my HD color grading monitor and on my projector (as it should), so I'd have no problem leaving it set at Quarter Res Debayer to enjoy the realtime playback while grading, then turn scaling output to match timeline when doing the final render.
Now for the 4K timeline (no one has been asking me for 8K outputs).
Playback with Full Res Debayer, with or without basic correction:
#1 19 fps
#2 14.5 fps
#3 14.5 fps
Note, there's really no reason for Full Res Debayer of 8K footage on a 4K timeline, but I wanted to see the numbers anyway.
Playback with Half Res Premium Debayer, with or without basic correction:
#1 19 fps
#2 14.5 fps
#3 14.5 fps
Playback with Half Res Good Debayer, with or without basic correction:
#1 19 fps
#2 15 fps
#3 14.5 fps
This time Full Res, Half Res Premium, and Half Res Good were the same. Ran tests twice to be sure.
Playback with Quarter Res Debayer, with or without basic correction:
#1 23.976 fps
#2 23.976 fps
#3 23.976 fps
Playback with Full Res Debayer, with basic correction & TNR:
#1 11.5 fps (fluctuated)
#2 11 fps
#3 12 fps
Playback with Half Res Premium Debayer, with basic correction & TNR:
#1 ~16.5 fps (fluctuated)
#2 ~13.5 fps (fluctuated)
#3 ~13 fps (fluctuated)
Playback with Half Res Good Debayer, with basic correction & TNR:
#1 ~17 fps (fluctuated)
#2 ~14 fps (fluctuated)
#3 ~13.5 fps (fluctuated)
Playback with Quarter Res Debayer, with basic correction & TNR:
#1 23.976 fps
#2 23.976 fps
#3 23.976 fps
Rendering the 4K timeline to a 4K ProRes 422HQ .mov results in 8.5 fps at Half Res Premium debayer. Full Res Debayer was 7.5 fps. That is with correction and TNR.
With the 4K timeline, the fan on the Radeon VII did not get loud like with the 8K timeline. With Red 8K footage I'd probably work in a 4K timeline (my clients right now are always 4K outputs or lower) and would use Quarter Res Debayer until final output, and that would even allow me to do some NR. I'm pretty happy with that.
I believe Resolve may be doing some auto debayer settings with Red footage, and it must be based on the timeline or on the output scaling settings. Otherwise I don't know why the results of the full res and half res premium debayer settings are always the same.