Unable to have two GPUs (RX 5700 XT & RX 580) recognized by Blender simultaneously

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21

@joules would you be able to explain us a little more on how to do a patch for 19.50?
Thanks a lot!

22

@rlamorato I thought it was working for you? This patch only applies against 19.30.
Have to check. Tomorrow. Can you run clinfo and paste it?

23

It did work somehow… I was able to render using the 2 GPU’s with the default scene but anything more complex the render will: hang on the first two tiles or all the tiles will render except for one or render doesn’t even start. I haven’t done any extensive tests to know what causes the problems exactly. All I know is that clinfo detects the two cards, but rendering with both is a little problematic.

This is on 19.30 with the patch you supplied.

clinfo.xml (17.6 KB)

24

Well I have good news and bad news.

@rlamorato Not really sure. Please try latest 19.50 and clinfo however see bellow for how I set up opencl.

The good news is I no longer need this hack.

The bad news is I’m having trouble tracking down why.

I went about d/l 19.50 and installing it. Straight away clinfo showed 2 platforms and both cards. Blender recognized both. Went back to 19.30 same thing.
But I’ve done alot of things in the last few months:

  • Swapped pcie slots between cards.
  • Change primary display pci slot in the bios.
  • Mess about bios alot
  • Installed windows 10
  • flashed vbios on my vega to latest (on their forum) - But reverted back to previous vbios and still had no issues.
  • Plus a few more things (kxstudio, low latency kernel)

I’ve spent a couple of hours, without pulling my cards to figure it out. And no such luck. It could be any of these, or none.
We could have been very fringe cases here and why this hack worked is now a mystery I’m afraid.
As for the latest navi cards. I don’t have one to test.
My setup for OpenCL and amdgpu:

  • Linux joules-X8DAH 5.3.0-24-lowlatency #26~18.04.2-Ubuntu SMP PREEMPT Tue Nov 26 14:39:35 UTC 2019 x86_64 x86_64 x86_64 GNU/Linux
  • Repo: deb http://ppa.launchpad.net/oibaf/graphics-drivers/ubuntu bionic main
  • Manually extract the opencl-*.deb using dpkg -x and place them in a /opt/amdgpu-pro-19.30-opencl/lib along with an entry for ld.so.conf.d then ldconfig
  • Make sure there’s proper entries for the libs in /etc/OpenCL/vendors
  • I use the OPENCL loader (libOpenCL.so.1.0.0) that comes with the OS not the one supplied with the pro drivers that would be in package ocl-icd-libopencl1
  • I now recommend having a copy of windows 10 - to at least compare issues between OS’s

Not sure what else to suggest, other than I’ll be back here if I come across any issues in relation to this.
Good luck.