Originally Posted by noob00224
I had a similar problem playing 4K HDR 60FPS and it was due to the PCI Express bus being stuck at x4, where it should be at x16. So bandwith problem.
Turned out the CPU was causing it.
GPU Z displays the PCI Express Bus multiplier. You can press the question mark next to the Bus and GPU Z will run a small test which will max it out (some cards lower it to x4 during idle). It should go up to x16 immediately.
Thanks, but it's not that, it stays in both modes at: PCIex16 3.0 @ x16 3.0 (it says "@ x16 1.1" in idle)
Originally Posted by mightyhuhn
just to make that obsoletely clear i'm not saying that copyback has the same speed but it is clearly in the real not significant on performance cards the numbers are deceiving. uploading "textures" is simply something GPU are good at and they learned downloading to over the past 10 years. d3d11 makes a more notable difference for iGPU which still can do the copyback operation and they have about 5 or more % of the performance of an 1060.
I understand what you say, I only tell you what I see here.
Here's another test:
- 4GB/55 min file (10.2Mbps video) 24p 4K SDR (not even 60p)
- played back on 1080p monitor in window mode (not fullscreen to give the GPU more work) (smoothmotion is not enabled)
-- scaled to: 1627x915 (the saved OSD image doesn't show this for whatever reason)
- gpu usage results: dxva2-cp ~87% ; d3d11 ~82%
-- you can see this on both graphs: left from the center is dxva2-cp, right is d3d11
So, the difference is around 5% (due to less bandwidth), but as you said, it's still a big diff.
Now, I'm curious your graphs, guys