Running windows 10, and that isn’t affecting performance. Based on Blender Dev checks it was related to one of the new noise shaders. Though they improved speeds to near old ones, they are still not there.
While thinking I had a “simialr” experience to what you are initiall seeing.
when I open a fresh blender build, the settings to use the GPU are not actually being taken.
In the settings i had to uncheck, save, then check again and save. then i could render with the GPU
I downloaded 2.81a. Now the two GPU tiles are rendering with my CPUs as expected.
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I rendered with RX570 8GB card (GPU Only, 2.81a, 256x256 tiles) and take same result of my old Geforce 670 card (CPU + GPU, 2.80, 32x32 tiles) . And my computer sometimes freeze when use “CPU + GPU” mode. Best result produced with “Only GPU” mode. RX570 nearly two times performanced card than Geforce 670, but in Blender Cycles, give same performance.
Intresting… wonder if it is something with GPU driver?
can you tell me which OS and what scene you tested?
Win 7 64-bit, 1.9.12.1 driver. I’m not use AMD card too much before. I don’t know this problem based driver or another thing.
So did another batch of GPU renders.with my Vega 64.
Windows 10, driver 19.9.2
Classroom scene with 150 samples and 512 tiles. - I matched settings that techguage had during their viewport render results. to see any differences.
All my tests below are with the kernel compile excluded (e.g re-render of the scene)
2.80 - 97s – techguage had 115s but they probably had kernel compile included
2.81a - 139s
2.82 - 144s
Original issue was over 2x slowdown, so expected 2.81a was in the 180s range.
So though they did include a partial fix it is still not where it should be (where 2.80 was)
I will admit… even with AMD funds, Blenders interest in investing time/resources to improve AMD performance is currently lacking.
I’m really debating the AMD Pro Render due to it’s overall work. including the Hybrid Rendering.
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I will test this scene. But I tried 2.80 and not too much change, only little fast.
I got better result than RX570 with “Geforce 670 + CPU”.
so CPU+GPU render is … intresting.
With AMD, the small tiles (32x32 or lower) that CPU needs, are not working great on the AMD GPU
With Nvidia, 32x32 tiles (or lower) work great as such the GPU and CPU are used to their max.
No, I use 128x128 wirth AMD, but Blender developer says not work good with OpenCL 1.1, and my CPU only support OpenCL 1.1, and mostly freeze computer when “RX570 + CPU” render.
Are you know best driver for OpenCL performance?
That is strange feedback. What CPU do you have?
main issue is that all CPU’s render best at 32x32 tiles or even 16x16 tiles. 128x128 tiles for CPU is … generally not great. The GPU won’t have time to be utilized the best.
Intel I5-2500K.
32x32 with ATI cards too slow for me, but good for Geforce.
Classroom Scene (256x256, GPU Only) = 10 minute 21 second. I didn’t change any settings except Tiles.
And the situation with Nvidia video cards, how about new versions of the blender?
Do you have the same problems with a drop in rendering speed?
nVidia has no problem. Like ever.
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I’ve been using blender sine … well too long to admit, and yes Nvidia had plenty of issues in the past. Windows Unix, you name it they had their share.
Only in the recent few years Nvidia actually spend money to improve the coding.
Sometimes AMD sometiems Nvidia had the “higher ground” on performance.
So I can’t agree with “nvidia has no problem, like ever.” But they are defintiely (currently) ahead of AMD, there is no doubt about it (as long as they dont’ mess up their drivers again)
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The drop in performance is only on OpenCL rendering pipeline. SO affects AMD the most. Unsure how Nvidia usign OpenCL is actually responding as no one posted results.
THe issue based on developers is caused only by one shader. the Noise shader that they added recently is simply no performance optimizations from Blenders perspective.
So technically not even OpenCL issue, just that Blender team is concentrating on other things and released uncompleted noise shader without proper testing.
They already “ffixed” parts of it, but full fix should be in 2.82 (if all goes well) base don their notes in the bug reprot.
I fixed my problem. EFI BIOS occurs this problem. When I update to UEFI BIOS, problem fixed.
My RX570 graphic card best with “CPU + GPU 64x64 Tiles”.
BMW Demo:
2.80 => 03:20
2.81a => 03:53
Slow, but not very slow.
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Is this ever going to be fixed? Is it even being looked at?
I retested 2.8, 2.81, 2.82 and 2.83 and the performance is still abysmal with my AMD card.
YES… expected in 2.83. The below is the latest update by dev’s on my ticket.
https://developer.blender.org/T71479
" Marking as high priority since this is something we want to address for the 2.83 release. @Jeroen Bakker (jbakker) has submitted a patch to use OpenCL 2.0 which will helps, but currently requires some manual configuration which I’ll try to find an automatic solution for."
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