Only 1 of 2 Radeon 5700 XT recognized in lspci

[mariner92]

I have an ASRock X299 Steel Legend MB, with 2 - Radeon RX 5700 XT cards installed (all the power/lights are powered up on both boards), but only one is being recognized by 'lspci | grep VGA'.. any suggestions?

 

[mariner92]

just tested the 2nd graphics card and computer won't POST - fortunately just bought it so returning it won't be an issue. If I keep the remaining RX 5700 XT for my Windows guest, any suggestions for a good bang for the buck host GPU card (maybe around $250)?

 

[EarthDog]

I'm going to move this to the alternative OS section. Hopefully, we can get you some answers soon.

Offhand I'm not sure what works best with that OS... sorry.

 

[Ben333]

Level1Techs on Youtube has covered PCI-E passthrough \ SR-IOV for Linux hosts with Windows guests. That might be something to check out.

 

[mariner92]

So, it turns out it that the card that wasn't recognized was bad. So, after returning it, I have a RX5600XT in PCI slot 1 and a RX5700XT in PCI slot 3.

from lspci -nn -vvv

0f:00.0 VGA compatible controller [0300]: Advanced Micro Devices, Inc. [AMD/ATI] Navi 10 [Radeon RX 5600 OEM/5600 XT / 5700/5700 XT] [1002:731f] (rev ca) (prog-if 00 [VGA controller])
Subsystem: Tul Corporation / PowerColor Navi 10 [Radeon RX 5600 OEM/5600 XT / 5700/5700 XT] [148c:2402]
Control: I/O+ Mem+ BusMaster+ SpecCycle- MemWINV- VGASnoop- ParErr- Stepping- SERR- FastB2B- DisINTx+
Status: Cap+ 66MHz- UDF- FastB2B- ParErr- DEVSEL=fast >TAbort- <TAbort- <MAbort- >SERR- <PERR- INTx-
Latency: 0, Cache Line Size: 64 bytes
Interrupt: pin A routed to IRQ 94
Region 0: Memory at d0000000 (64-bit, prefetchable) [size=256M]
Region 2: Memory at e0000000 (64-bit, prefetchable) [size=2M]
Region 4: I/O ports at e000
Region 5: Memory at fcd00000 (32-bit, non-prefetchable) [size=512K]
Expansion ROM at 000c0000 [disabled] [size=128K]
Capabilities: <access denied>
Kernel driver in use: amdgpu
Kernel modules: amdgpu

*********************************************************************
12:00.0 VGA compatible controller [0300]: Advanced Micro Devices, Inc. [AMD/ATI] Navi 10 [Radeon RX 5600 OEM/5600 XT / 5700/5700 XT] [1002:731f] (rev c1) (prog-if 00 [VGA controller])
Subsystem: Tul Corporation / PowerColor Navi 10 [Radeon RX 5600 OEM/5600 XT / 5700/5700 XT] [148c:2398]
Control: I/O+ Mem+ BusMaster+ SpecCycle- MemWINV- VGASnoop- ParErr- Stepping- SERR- FastB2B- DisINTx+
Status: Cap+ 66MHz- UDF- FastB2B- ParErr- DEVSEL=fast >TAbort- <TAbort- <MAbort- >SERR- <PERR- INTx-
Latency: 0, Cache Line Size: 64 bytes
Interrupt: pin A routed to IRQ 127
Region 0: Memory at b0000000 (64-bit, prefetchable) [size=256M]
Region 2: Memory at c0000000 (64-bit, prefetchable) [size=2M]
Region 4: I/O ports at d000
Region 5: Memory at fcb00000 (32-bit, non-prefetchable) [size=512K]
Expansion ROM at fcb80000 [disabled] [size=128K]
Capabilities: <access denied>
Kernel driver in use: amdgpu
Kernel modules: amdgpu

from iommu.sh

#!/bin/bash
shopt -s nullglob
for d in /sys/kernel/iommu_groups/*/devices/*; do
n=${d#*/iommu_groups/*}; n=${n%%/*}
printf 'IOMMU Group %s ' "$n"
lspci -nns "${d##*/}"
done;

IOMMU Group 28 0f:00.0 VGA compatible controller [0300]: Advanced Micro Devices, Inc. [AMD/ATI] Navi 10 [Radeon RX 5600 OEM/5600 XT / 5700/5700 XT] [1002:731f] (rev ca)
IOMMU Group 32 12:00.0 VGA compatible controller [0300]: Advanced Micro Devices, Inc. [AMD/ATI] Navi 10 [Radeon RX 5600 OEM/5600 XT / 5700/5700 XT] [1002:731f] (rev c1)

Please note that in the IOMMU output the addresses are identical between rev ca and rev c1 vs the addresses being different in lspci output. My question is how can I pass-through rev ca card to my windows guest (the rev c1 card will remain my display for my Ubuntu 20.04 host).

Thoughts?