have a dual-GPU system on Ubuntu: an NVIDIA GTX 1650 and an AMD Radeon RX 6500 XT. I did not remove or replace the NVIDIA GPU; both are installed and detected.
The problem is that when I try to use the AMD GPU in PCSX2 or LSFG-VK, games crash or fail to launch. I want to understand whether this is caused by leftover NVIDIA settings, a broken Vulkan layer, or a wrong GPU selection in PCSX2/LSFG-VK.
My hardware
vulkaninfo --summary shows both GPUs:
NVIDIA GeForce GTX 1650
driverName = NVIDIA
AMD Radeon RX 6500 XT (RADV NAVI24)
driverName = radv
deviceType = PHYSICAL_DEVICE_TYPE_DISCRETE_GPU
So Linux sees the AMD GPU correctly, and it is using the open-source RADV Vulkan driver. But I still get crashes when I try to run games on it.�
PCSX2 settings
In PCSX2 → Settings → Graphics, I have:
Renderer: Vulkan
Adapter: I need to confirm whether to select AMD Radeon RX 6500 XT or leave it on Default
Internal Resolution: 2x Native
Skip Presenting Duplicate Frames: Enabled for LSFG
Allow Exclusive Fullscreen: Disallowed
VSync: Off
My question is: should I manually select the AMD Radeon RX 6500 XT as the Adapter in PCSX2, or leave it on Default/Automatic?
LSFG-VK error
I also use LSFG-VK, and Vulkan gives this error:
Failed to find 'vkGetInstanceProcAddr' in layer
"/home/polli/.local/share/vulkan/implicit_layer.d/../../../lib/liblsfg-vk-layer.so"
Skipping layer.
This means the LSFG-VK Vulkan layer is broken or incorrectly installed. I know I need to reinstall it, but I also want to know if this broken layer could be causing the crashes in PCSX2 or other games.
What I want to know
Should I select AMD Radeon RX 6500 XT as the Adapter in PCSX2, or leave it on Default?
Should I select the same AMD GPU in LSFG-VK UI?
Can LSFG-VK run on the NVIDIA GPU while PCSX2 renders on the AMD GPU, or do they need to be on the same GPU?
Could the broken LSFG-VK layer be causing the crashes even if I do not actively use it?
Do I need to remove any NVIDIA Vulkan layers or ICD files, even though I want to keep the NVIDIA GPU installed?
Is there a way to force Steam/Proton games to use the AMD GPU instead of NVIDIA?
What I already know
AMD gaming on Linux normally uses the open-source amdgpu kernel driver plus Mesa/RADV for Vulkan; RADV is included with Mesa and supports modern AMD GPUs.�
For Vulkan gaming, the usual packages are vulkan-tools, libvulkan1, and mesa-vulkan-drivers; the AMD proprietary stack is generally not required for normal gaming.�
nvidia-smi only shows NVIDIA GPUs, so it cannot tell me what is happening on the AMD side.