Ubuntu 20.04 with two GPUs OpenCL issue

jwh20

4/12/23, 12:32 PM

I have an ASUS AM4 TUF Gaming X570-Plus motherboard with AMD Ryzen 9 3900X CPU, 16GB of RAM running Ubuntu 20.04. I've had an AMD Radeon RX 6700 XT GPU installed and it all works great.

I recently picked up an ASUS TUF AMD Radeon RX 5600 XT GPU card and am trying to get both GPUs to work in the system.

When either card is installed alone, things work perfectly. But if I install both at the same time, I do get video output and the desktop but I'm having issues with the OpenCL interface. If I type clinfo it shows there are 0 devices.

I have plenty of power with a 1000W EVGA supply and am powering both cards with their own cable directly from the supply without using any splitters or extenders.

At this point I'm not sure if it's a MB BIOS setup issue, an OpenCL issue, an Ubuntu issue, or something else. So anything that points me in the right direction would be appreciated.

UPDATE: I haven't been able to get a 2nd GPU card that matches but I do have one other motherboard that has > 1 PCIe slot out of a Dell Optiplex 755 desktop. I have it loaded up with the same Ubuntu 20.04 and AMD drivers and I found that it works perfectly with either one card or both at the same time. I'm wondering now if the problem is the ASUS motherboard itself or its BIOS settings that are causing the problem.

0 + 0

graphics

opencl

radeon

drivers

20.04

Nmath

4/12/23, 12:36 PM

What are you trying to do with them? With multiple GPU settings, you're generally going to have a bad time if the cards are not identical. But it also depends on what you're trying to do. In some cases, more is not better

jwh20

4/12/23, 12:50 PM

I can try with two 5600 XT GPUs. I have one that I can borrow.

Elon Musk

I sit in a Tesla and translated this thread with Ai:

EN: Ubuntu 20.04 with two GPUs OpenCL issue

TH: Ubuntu 20.04 ที่มีปัญหา OpenCL GPU สองตัว

RO: Ubuntu 20.04 cu două GPU-uri problema OpenCL

RU: Ubuntu 20.04 с двумя GPU, проблема с OpenCL

VI: Ubuntu 20.04 với sự cố OpenCL hai GPU

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