Intel Arc Pro B60 stuck at PCIe Gen1 x1 and ~21GB VRAM in Proxmox

cjblank · March 16, 2026, 6:13pm

I need help with a couple recently purchased Intel Arc Pro B60s in my Proxmox system (EPYC 7K62, Supermicro H12SSL-i, 128GB ECC DDR4). I bought the ARKN variants from Newegg (product page) and started noticing issues pretty much right away.

My original plan was to pass them straight through to a VM for local inference using VFIO, but none of the Intel tools I tried, clinfo and the Level Zero tools, were picking them up as GPUs. Because of that I started digging into what the cards looked like from the host side.

That’s where things started looking weird. The PCIe link negotiation for both cards only shows Gen1 x1 at 2.5GT/s. I double checked the usual BIOS settings, Resizable BAR, Above 4G Decoding, SR-IOV support, and made sure all the x16 slots are forced to [x16] instead of [Auto]. None of that changed the link behavior.

I also noticed the card is being reported with about 21GB of VRAM instead of the 24GB listed on the product page. Funny enough, there’s a reviewer on the Newegg page saying they couldn’t get 24GB out of it either, along with this YouTube video.

At this point I’m not really sure where to go next. If anyone has experience getting these cards working properly in a setup like this, I’d appreciate the advice.

Here are some relevant details from what I’ve found so far:

root@proxmox:~# ./gpu_debug.sh
========== SYSTEM ==========

### COMMAND:
uname -r
### OUTPUT:
6.17.13-2-pve

### COMMAND:
pveversion
### OUTPUT:
pve-manager/9.1.6/71482d1833ded40a (running kernel: 6.17.13-2-pve)

### COMMAND:
cat /proc/cmdline
### OUTPUT:
BOOT_IMAGE=/boot/vmlinuz-6.17.13-2-pve root=/dev/mapper/pve-root ro quiet amd_iommu=on iommu=pt pcie_aspm=off pcie_acs_override=downstream,multifunction pci=realloc

### COMMAND:
lscpu | grep 'Model name'
### OUTPUT:
Model name:                              AMD EPYC 7K62 48-Core Processor

### COMMAND:
dmidecode -t baseboard | grep -E 'Manufacturer|Product|Version'
### OUTPUT:
        Manufacturer: Supermicro
        Product Name: H12SSL-i
        Version: 1.10

========== GPU DEVICES ==========

### COMMAND:
lspci -nn | grep -E 'VGA|3D'
### OUTPUT:
43:00.0 VGA compatible controller [0300]: ASPEED Technology, Inc. ASPEED Graphics Family [1a03:2000] (rev 41)
83:00.0 VGA compatible controller [0300]: Intel Corporation Battlemage G21 [Intel Graphics] [8086:e211]
c1:00.0 VGA compatible controller [0300]: NVIDIA Corporation GB205 [GeForce RTX 5070] [10de:2f04] (rev a1)
c4:00.0 VGA compatible controller [0300]: Intel Corporation Battlemage G21 [Intel Graphics] [8086:e211]

### COMMAND:
lspci -nnk -d 8086:e211
### OUTPUT:
83:00.0 VGA compatible controller [0300]: Intel Corporation Battlemage G21 [Intel Graphics] [8086:e211]
        Subsystem: Device [207e:a023]
        Kernel driver in use: xe
        Kernel modules: xe
c4:00.0 VGA compatible controller [0300]: Intel Corporation Battlemage G21 [Intel Graphics] [8086:e211]
        Subsystem: Device [207e:a023]
        Kernel driver in use: xe
        Kernel modules: xe

### COMMAND:
lspci -tv
### OUTPUT:
-+-[0000:00]-+-00.0  Advanced Micro Devices, Inc. [AMD] Starship/Matisse Root Complex
 |           +-00.2  Advanced Micro Devices, Inc. [AMD] Starship/Matisse IOMMU
 |           +-01.0  Advanced Micro Devices, Inc. [AMD] Starship/Matisse PCIe Dummy Host Bridge
 |           +-02.0  Advanced Micro Devices, Inc. [AMD] Starship/Matisse PCIe Dummy Host Bridge
 |           +-03.0  Advanced Micro Devices, Inc. [AMD] Starship/Matisse PCIe Dummy Host Bridge
 |           +-03.3-[01]----00.0  Sandisk Corp WD Black SN770 / PC SN740 256GB / PC SN560 (DRAM-less) NVMe SSD
 |           +-03.4-[02]----00.0  Samsung Electronics Co Ltd NVMe SSD Controller S4LV008[Pascal]
 |           +-04.0  Advanced Micro Devices, Inc. [AMD] Starship/Matisse PCIe Dummy Host Bridge
 |           +-05.0  Advanced Micro Devices, Inc. [AMD] Starship/Matisse PCIe Dummy Host Bridge
 |           +-07.0  Advanced Micro Devices, Inc. [AMD] Starship/Matisse PCIe Dummy Host Bridge
 |           +-07.1-[03]--+-00.0  Advanced Micro Devices, Inc. [AMD] Starship/Matisse PCIe Dummy Function
 |           |            \-00.2  Advanced Micro Devices, Inc. [AMD] Starship/Matisse PTDMA
 |           +-08.0  Advanced Micro Devices, Inc. [AMD] Starship/Matisse PCIe Dummy Host Bridge
 |           +-08.1-[04]--+-00.0  Advanced Micro Devices, Inc. [AMD] Starship/Matisse Reserved SPP
 |           |            +-00.2  Advanced Micro Devices, Inc. [AMD] Starship/Matisse PTDMA
 |           |            \-00.3  Advanced Micro Devices, Inc. [AMD] Starship USB 3.0 Host Controller
 |           +-14.0  Advanced Micro Devices, Inc. [AMD] FCH SMBus Controller
 |           +-14.3  Advanced Micro Devices, Inc. [AMD] FCH LPC Bridge
 |           +-18.0  Advanced Micro Devices, Inc. [AMD] Starship Device 24; Function 0
 |           +-18.1  Advanced Micro Devices, Inc. [AMD] Starship Device 24; Function 1
 |           +-18.2  Advanced Micro Devices, Inc. [AMD] Starship Device 24; Function 2
 |           +-18.3  Advanced Micro Devices, Inc. [AMD] Starship Device 24; Function 3
 |           +-18.4  Advanced Micro Devices, Inc. [AMD] Starship Device 24; Function 4
 |           +-18.5  Advanced Micro Devices, Inc. [AMD] Starship Device 24; Function 5
 |           +-18.6  Advanced Micro Devices, Inc. [AMD] Starship Device 24; Function 6
 |           \-18.7  Advanced Micro Devices, Inc. [AMD] Starship Device 24; Function 7
 +-[0000:40]-+-00.0  Advanced Micro Devices, Inc. [AMD] Starship/Matisse Root Complex
 |           +-00.2  Advanced Micro Devices, Inc. [AMD] Starship/Matisse IOMMU
 |           +-01.0  Advanced Micro Devices, Inc. [AMD] Starship/Matisse PCIe Dummy Host Bridge
 |           +-02.0  Advanced Micro Devices, Inc. [AMD] Starship/Matisse PCIe Dummy Host Bridge
 |           +-03.0  Advanced Micro Devices, Inc. [AMD] Starship/Matisse PCIe Dummy Host Bridge
 |           +-03.3-[41]----00.0  ASMedia Technology Inc. ASM1042A USB 3.0 Host Controller
 |           +-03.4-[42-43]----00.0-[43]----00.0  ASPEED Technology, Inc. ASPEED Graphics Family
 |           +-03.5-[44]----00.0  ASMedia Technology Inc. ASM1042A USB 3.0 Host Controller
 |           +-03.6-[45]--+-00.0  Broadcom Inc. and subsidiaries NetXtreme BCM5720 Gigabit Ethernet PCIe
 |           |            \-00.1  Broadcom Inc. and subsidiaries NetXtreme BCM5720 Gigabit Ethernet PCIe
 |           +-04.0  Advanced Micro Devices, Inc. [AMD] Starship/Matisse PCIe Dummy Host Bridge
 |           +-05.0  Advanced Micro Devices, Inc. [AMD] Starship/Matisse PCIe Dummy Host Bridge
 |           +-07.0  Advanced Micro Devices, Inc. [AMD] Starship/Matisse PCIe Dummy Host Bridge
 |           +-07.1-[46]--+-00.0  Advanced Micro Devices, Inc. [AMD] Starship/Matisse PCIe Dummy Function
 |           |            \-00.2  Advanced Micro Devices, Inc. [AMD] Starship/Matisse PTDMA
 |           +-08.0  Advanced Micro Devices, Inc. [AMD] Starship/Matisse PCIe Dummy Host Bridge
 |           +-08.1-[47]--+-00.0  Advanced Micro Devices, Inc. [AMD] Starship/Matisse Reserved SPP
 |           |            +-00.1  Advanced Micro Devices, Inc. [AMD] Starship/Matisse Cryptographic Coprocessor PSPCPP
 |           |            +-00.2  Advanced Micro Devices, Inc. [AMD] Starship/Matisse PTDMA
 |           |            \-00.3  Advanced Micro Devices, Inc. [AMD] Starship USB 3.0 Host Controller
 |           +-08.2-[48]----00.0  Advanced Micro Devices, Inc. [AMD] FCH SATA Controller [AHCI mode]
 |           \-08.3-[49]----00.0  Advanced Micro Devices, Inc. [AMD] FCH SATA Controller [AHCI mode]
 +-[0000:80]-+-00.0  Advanced Micro Devices, Inc. [AMD] Starship/Matisse Root Complex
 |           +-00.2  Advanced Micro Devices, Inc. [AMD] Starship/Matisse IOMMU
 |           +-01.0  Advanced Micro Devices, Inc. [AMD] Starship/Matisse PCIe Dummy Host Bridge
 |           +-01.1-[81-84]----00.0-[82-84]--+-01.0-[83]----00.0  Intel Corporation Battlemage G21 [Intel Graphics]
 |           |                               \-02.0-[84]----00.0  Intel Corporation Device e2f7
 |           +-02.0  Advanced Micro Devices, Inc. [AMD] Starship/Matisse PCIe Dummy Host Bridge
 |           +-03.0  Advanced Micro Devices, Inc. [AMD] Starship/Matisse PCIe Dummy Host Bridge
 |           +-04.0  Advanced Micro Devices, Inc. [AMD] Starship/Matisse PCIe Dummy Host Bridge
 |           +-05.0  Advanced Micro Devices, Inc. [AMD] Starship/Matisse PCIe Dummy Host Bridge
 |           +-07.0  Advanced Micro Devices, Inc. [AMD] Starship/Matisse PCIe Dummy Host Bridge
 |           +-07.1-[85]--+-00.0  Advanced Micro Devices, Inc. [AMD] Starship/Matisse PCIe Dummy Function
 |           |            \-00.2  Advanced Micro Devices, Inc. [AMD] Starship/Matisse PTDMA
 |           +-08.0  Advanced Micro Devices, Inc. [AMD] Starship/Matisse PCIe Dummy Host Bridge
 |           +-08.1-[86]--+-00.0  Advanced Micro Devices, Inc. [AMD] Starship/Matisse Reserved SPP
 |           |            \-00.2  Advanced Micro Devices, Inc. [AMD] Starship/Matisse PTDMA
 |           +-08.2-[87]----00.0  Advanced Micro Devices, Inc. [AMD] FCH SATA Controller [AHCI mode]
 |           \-08.3-[88]----00.0  Advanced Micro Devices, Inc. [AMD] FCH SATA Controller [AHCI mode]
 \-[0000:c0]-+-00.0  Advanced Micro Devices, Inc. [AMD] Starship/Matisse Root Complex
             +-00.2  Advanced Micro Devices, Inc. [AMD] Starship/Matisse IOMMU
             +-01.0  Advanced Micro Devices, Inc. [AMD] Starship/Matisse PCIe Dummy Host Bridge
             +-01.1-[c1]--+-00.0  NVIDIA Corporation GB205 [GeForce RTX 5070]
             |            \-00.1  NVIDIA Corporation Device 2f80
             +-02.0  Advanced Micro Devices, Inc. [AMD] Starship/Matisse PCIe Dummy Host Bridge
             +-03.0  Advanced Micro Devices, Inc. [AMD] Starship/Matisse PCIe Dummy Host Bridge
             +-03.1-[c2-c5]----00.0-[c3-c5]--+-01.0-[c4]----00.0  Intel Corporation Battlemage G21 [Intel Graphics]
             |                               \-02.0-[c5]----00.0  Intel Corporation Device e2f7
             +-04.0  Advanced Micro Devices, Inc. [AMD] Starship/Matisse PCIe Dummy Host Bridge
             +-05.0  Advanced Micro Devices, Inc. [AMD] Starship/Matisse PCIe Dummy Host Bridge
             +-07.0  Advanced Micro Devices, Inc. [AMD] Starship/Matisse PCIe Dummy Host Bridge
             +-07.1-[c6]--+-00.0  Advanced Micro Devices, Inc. [AMD] Starship/Matisse PCIe Dummy Function
             |            \-00.2  Advanced Micro Devices, Inc. [AMD] Starship/Matisse PTDMA
             +-08.0  Advanced Micro Devices, Inc. [AMD] Starship/Matisse PCIe Dummy Host Bridge
             \-08.1-[c7]--+-00.0  Advanced Micro Devices, Inc. [AMD] Starship/Matisse Reserved SPP
                          \-00.2  Advanced Micro Devices, Inc. [AMD] Starship/Matisse PTDMA

========== PCIe LINK STATE ==========

### COMMAND:
lspci -vv -s 83:00.0 | grep -E 'LnkCap:|LnkSta:|LnkCap2:'
### OUTPUT:
                LnkCap: Port #0, Speed 2.5GT/s, Width x1, ASPM L0s L1, Exit Latency L0s <64ns, L1 <1us
                LnkSta: Speed 2.5GT/s, Width x1
                LnkCap2: Supported Link Speeds: 2.5GT/s, Crosslink- Retimer- 2Retimers- DRS-

### COMMAND:
lspci -vv -s c4:00.0 | grep -E 'LnkCap:|LnkSta:|LnkCap2:'
### OUTPUT:
                LnkCap: Port #0, Speed 2.5GT/s, Width x1, ASPM L0s L1, Exit Latency L0s <64ns, L1 <1us
                LnkSta: Speed 2.5GT/s, Width x1
                LnkCap2: Supported Link Speeds: 2.5GT/s, Crosslink- Retimer- 2Retimers- DRS-

========== BAR / VRAM APERTURE ==========

### COMMAND:
lspci -vv -s 83:00.0 | grep -E 'Region 2|Resizable BAR'
### OUTPUT:
        Region 2: Memory at 1e800000000 (64-bit, prefetchable) [size=32G]
        Capabilities: [420 v1] Physical Resizable BAR
        Capabilities: [220 v1] Virtual Resizable BAR
                Region 2: Memory at 000001f000000000 (64-bit, prefetchable)

### COMMAND:
lspci -vv -s c4:00.0 | grep -E 'Region 2|Resizable BAR'
### OUTPUT:
        Region 2: Memory at 16000000000 (64-bit, prefetchable) [size=32G]
        Capabilities: [420 v1] Physical Resizable BAR
        Capabilities: [220 v1] Virtual Resizable BAR
                Region 2: Memory at 0000016800000000 (64-bit, prefetchable)

========== VRAM DETECTED BY XE DRIVER ==========

### COMMAND:
dmesg | grep -E 'VRAM\[|VISIBLE VRAM'
### OUTPUT:
[   10.962210] xe 0000:c4:00.0: [drm] VISIBLE VRAM: 0x0000016000000000, 0x0000000800000000
[   10.962245] xe 0000:c4:00.0: [drm] VRAM[0]: Actual physical size 0x0000000540000000, usable size exclude stolen 0x000000053a600000, CPU accessible size 0x000000053a600000
[   10.962250] xe 0000:c4:00.0: [drm] VRAM[0]: DPA range: [0x0000000000000000-540000000], io range: [0x0000016000000000-1653a600000]
[   10.962254] xe 0000:c4:00.0: [drm] VRAM[0]: Actual physical size 0x0000000540000000, usable size exclude stolen 0x000000053a600000, CPU accessible size 0x000000053a600000
[   10.962257] xe 0000:c4:00.0: [drm] VRAM[0]: DPA range: [0x0000000000000000-540000000], io range: [0x0000016000000000-1653a600000]
[   11.680582] xe 0000:83:00.0: [drm] VISIBLE VRAM: 0x000001e800000000, 0x0000000800000000
[   11.680700] xe 0000:83:00.0: [drm] VRAM[0]: Actual physical size 0x0000000540000000, usable size exclude stolen 0x000000053a600000, CPU accessible size 0x000000053a600000
[   11.680704] xe 0000:83:00.0: [drm] VRAM[0]: DPA range: [0x0000000000000000-540000000], io range: [0x000001e800000000-1ed3a600000]
[   11.680709] xe 0000:83:00.0: [drm] VRAM[0]: Actual physical size 0x0000000540000000, usable size exclude stolen 0x000000053a600000, CPU accessible size 0x000000053a600000
[   11.680712] xe 0000:83:00.0: [drm] VRAM[0]: DPA range: [0x0000000000000000-540000000], io range: [0x000001e800000000-1ed3a600000]

========== XE DRIVER STATE ==========

### COMMAND:
modinfo xe | grep -E 'filename|vermagic|srcversion'
### OUTPUT:
filename:       /lib/modules/6.17.13-2-pve/kernel/drivers/gpu/drm/xe/xe.ko
srcversion:     9DF73FAD15D81C9378B16E4
vermagic:       6.17.13-2-pve SMP preempt mod_unload modversions

### COMMAND:
dmesg | grep -E 'xe .*drm'
### OUTPUT:
[   10.960229] xe 0000:c4:00.0: [drm] Running in SR-IOV PF mode
[   10.960461] xe 0000:c4:00.0: [drm] Found battlemage (device ID e211) discrete display version 14.01 stepping B0
[   10.962210] xe 0000:c4:00.0: [drm] VISIBLE VRAM: 0x0000016000000000, 0x0000000800000000
[   10.962245] xe 0000:c4:00.0: [drm] VRAM[0]: Actual physical size 0x0000000540000000, usable size exclude stolen 0x000000053a600000, CPU accessible size 0x000000053a600000
[   10.962250] xe 0000:c4:00.0: [drm] VRAM[0]: DPA range: [0x0000000000000000-540000000], io range: [0x0000016000000000-1653a600000]
[   10.962254] xe 0000:c4:00.0: [drm] VRAM[0]: Actual physical size 0x0000000540000000, usable size exclude stolen 0x000000053a600000, CPU accessible size 0x000000053a600000
[   10.962257] xe 0000:c4:00.0: [drm] VRAM[0]: DPA range: [0x0000000000000000-540000000], io range: [0x0000016000000000-1653a600000]
[   11.118986] xe 0000:c4:00.0: [drm] GT0: Using GuC firmware from xe/bmg_guc_70.bin version 70.55.3
[   11.132091] xe 0000:c4:00.0: [drm] Finished loading DMC firmware i915/bmg_dmc.bin (v2.6)
[   11.538272] xe 0000:c4:00.0: [drm] GT0: ccs2 fused off
[   11.538277] xe 0000:c4:00.0: [drm] GT0: ccs3 fused off
[   11.566086] xe 0000:c4:00.0: [drm] GT1: Using GuC firmware from xe/bmg_guc_70.bin version 70.55.3
[   11.574804] xe 0000:c4:00.0: [drm] GT1: Using HuC firmware from xe/bmg_huc.bin version 8.2.10
[   11.587116] xe 0000:c4:00.0: [drm] GT1: vcs1 fused off
[   11.587120] xe 0000:c4:00.0: [drm] GT1: vcs3 fused off
[   11.587123] xe 0000:c4:00.0: [drm] GT1: vcs4 fused off
[   11.587126] xe 0000:c4:00.0: [drm] GT1: vcs5 fused off
[   11.587128] xe 0000:c4:00.0: [drm] GT1: vcs6 fused off
[   11.587131] xe 0000:c4:00.0: [drm] GT1: vcs7 fused off
[   11.587134] xe 0000:c4:00.0: [drm] GT1: vecs2 fused off
[   11.587137] xe 0000:c4:00.0: [drm] GT1: vecs3 fused off
[   11.623751] xe 0000:c4:00.0: [drm] Registered 4 planes with drm panic
[   11.663881] xe 0000:c4:00.0: [drm] Cannot find any crtc or sizes
[   11.676439] xe 0000:c4:00.0: [drm] Using mailbox commands for power limits
[   11.676905] xe 0000:c4:00.0: [drm] PL2 is supported on channel 0
[   11.678699] xe 0000:83:00.0: [drm] Running in SR-IOV PF mode
[   11.678906] xe 0000:83:00.0: [drm] Found battlemage (device ID e211) discrete display version 14.01 stepping B0
[   11.680582] xe 0000:83:00.0: [drm] VISIBLE VRAM: 0x000001e800000000, 0x0000000800000000
[   11.680700] xe 0000:83:00.0: [drm] VRAM[0]: Actual physical size 0x0000000540000000, usable size exclude stolen 0x000000053a600000, CPU accessible size 0x000000053a600000
[   11.680704] xe 0000:83:00.0: [drm] VRAM[0]: DPA range: [0x0000000000000000-540000000], io range: [0x000001e800000000-1ed3a600000]
[   11.680709] xe 0000:83:00.0: [drm] VRAM[0]: Actual physical size 0x0000000540000000, usable size exclude stolen 0x000000053a600000, CPU accessible size 0x000000053a600000
[   11.680712] xe 0000:83:00.0: [drm] VRAM[0]: DPA range: [0x0000000000000000-540000000], io range: [0x000001e800000000-1ed3a600000]
[   11.743874] xe 0000:c4:00.0: [drm] Cannot find any crtc or sizes
[   11.783868] xe 0000:c4:00.0: [drm] Cannot find any crtc or sizes
[   11.849326] xe 0000:83:00.0: [drm] Finished loading DMC firmware i915/bmg_dmc.bin (v2.6)
[   11.851220] xe 0000:83:00.0: [drm] GT0: Using GuC firmware from xe/bmg_guc_70.bin version 70.55.3
[   12.267897] xe 0000:83:00.0: [drm] GT0: ccs2 fused off
[   12.267903] xe 0000:83:00.0: [drm] GT0: ccs3 fused off
[   12.295326] xe 0000:83:00.0: [drm] GT1: Using GuC firmware from xe/bmg_guc_70.bin version 70.55.3
[   12.298426] xe 0000:83:00.0: [drm] GT1: Using HuC firmware from xe/bmg_huc.bin version 8.2.10
[   12.310724] xe 0000:83:00.0: [drm] GT1: vcs1 fused off
[   12.310729] xe 0000:83:00.0: [drm] GT1: vcs3 fused off
[   12.310732] xe 0000:83:00.0: [drm] GT1: vcs4 fused off
[   12.310735] xe 0000:83:00.0: [drm] GT1: vcs5 fused off
[   12.310737] xe 0000:83:00.0: [drm] GT1: vcs6 fused off
[   12.310740] xe 0000:83:00.0: [drm] GT1: vcs7 fused off
[   12.310742] xe 0000:83:00.0: [drm] GT1: vecs2 fused off
[   12.310745] xe 0000:83:00.0: [drm] GT1: vecs3 fused off
[   12.347087] xe 0000:83:00.0: [drm] Registered 4 planes with drm panic
[   12.426868] xe 0000:83:00.0: [drm] Cannot find any crtc or sizes
[   12.429864] xe 0000:83:00.0: [drm] Using mailbox commands for power limits
[   12.430327] xe 0000:83:00.0: [drm] PL2 is supported on channel 0
[   12.466870] xe 0000:83:00.0: [drm] Cannot find any crtc or sizes

========== FIRMWARE ==========

### COMMAND:
dmesg | grep -Ei 'guc|huc|gsc'
### OUTPUT:
[   11.118986] xe 0000:c4:00.0: [drm] GT0: Using GuC firmware from xe/bmg_guc_70.bin version 70.55.3
[   11.566086] xe 0000:c4:00.0: [drm] GT1: Using GuC firmware from xe/bmg_guc_70.bin version 70.55.3
[   11.574804] xe 0000:c4:00.0: [drm] GT1: Using HuC firmware from xe/bmg_huc.bin version 8.2.10
[   11.851220] xe 0000:83:00.0: [drm] GT0: Using GuC firmware from xe/bmg_guc_70.bin version 70.55.3
[   12.295326] xe 0000:83:00.0: [drm] GT1: Using GuC firmware from xe/bmg_guc_70.bin version 70.55.3
[   12.298426] xe 0000:83:00.0: [drm] GT1: Using HuC firmware from xe/bmg_huc.bin version 8.2.10
[   12.486910] 0x000000001000-0x00000054e000 : "xe.nvm.50176.GSC"
[   12.498589] 0x000000001000-0x00000054e000 : "xe.nvm.33536.GSC"

========== DRM DEVICES ==========

### COMMAND:
ls -l /dev/dri
### OUTPUT:
total 0
drwxr-xr-x 2 root root        140 Mar 16 11:26 by-path
crw-rw---- 1 root video  226,   0 Mar 16 11:26 card0
crw-rw---- 1 root video  226,   1 Mar 16 11:26 card1
crw-rw---- 1 root video  226,   2 Mar 16 11:26 card2
crw-rw---- 1 root render 226, 128 Mar 16 11:26 renderD128
crw-rw---- 1 root render 226, 129 Mar 16 11:26 renderD129

========== IOMMU GROUPS ==========

### COMMAND:
find /sys/kernel/iommu_groups -type l | grep 83:00.0
### OUTPUT:
/sys/kernel/iommu_groups/37/devices/0000:83:00.0

### COMMAND:
find /sys/kernel/iommu_groups -type l | grep c4:00.0
### OUTPUT:
/sys/kernel/iommu_groups/16/devices/0000:c4:00.0

========== COMPLETE ==========
Diagnostic output saved to gpu_diag_20260316_121003.txt
root@proxmox:~#

anlin · March 18, 2026, 3:34pm

The gen1 x1 link status is a known quirk with Arc cards. The PCIe bridge upstream of the G21 device should show the actual link status (16 GT/s x8 would be expected in your case).

cjblank · March 18, 2026, 5:36pm

Yeah, I figured out that I needed to load the cards into Intel Arc Pro Graphics on a Windows machine in order to update the firmware and disable the ECC reservation on the VRAM so that all of the capacity is usable. I have yet to figure out how to pass the whole GPU into a VM in Proxmox due to the weird bridge situation (I couldn’t change the driver for the root port of the bridge from ‘pcieport’ to ‘vfio-pci’ so that it would be selectable as a PCI device), so I just created an LXC and it seems to be working fine for the time being

Strawberry · March 18, 2026, 8:18pm

Hmm. Is the passthrough situation weird? I didn’t have to change anything at all for my arc pro cards, it just worked. SR-IOV needs a tiny bit of fiddling but even that iirc is out of the box nearly.

cjblank · March 19, 2026, 1:02am

I was initially using an Ubuntu 25.04 VM and the xe driver wouldn’t bind to the devices that I passed through correctly. I just tried spinning up a new VM with a 25.10 image earlier today and everything worked fine in terms of llama.cpp using the GPU properly.

BillM · July 17, 2026, 8:32am

I have the same with a B50 Pro, the link state shows 2.5GT/s at PCIe x1:

# lspci -s b5:00.0 -vv
b5:00.0 VGA compatible controller: Intel Corporation Battlemage G21 [Intel Graphics] (prog-if 00 [VGA controller])
        Subsystem: Intel Corporation Device 1114
        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: 32 bytes
        Interrupt: pin ? routed to IRQ 185
        NUMA node: 0
        IOMMU group: 4
        Region 0: Memory at fa000000 (64-bit, non-prefetchable) [size=16M]
        Region 2: Memory at 38f800000000 (64-bit, prefetchable) [size=16G]
        Expansion ROM at fb000000 [disabled] [size=2M]
        Capabilities: [40] Vendor Specific Information: Len=0c <?>
        Capabilities: [70] Express (v2) Endpoint, IntMsgNum 0
                DevCap: MaxPayload 256 bytes, PhantFunc 0, Latency L0s unlimited, L1 unlimited
                        ExtTag+ AttnBtn- AttnInd- PwrInd- RBE+ FLReset+ SlotPowerLimit 0W TEE-IO-
                DevCtl: CorrErr- NonFatalErr- FatalErr+ UnsupReq-
                        RlxdOrd+ ExtTag+ PhantFunc- AuxPwr- NoSnoop+ FLReset-
                        MaxPayload 256 bytes, MaxReadReq 512 bytes
                DevSta: CorrErr- NonFatalErr- FatalErr- UnsupReq- AuxPwr- TransPend-
                LnkCap: Port #0, Speed 2.5GT/s, Width x1, ASPM L0s L1, Exit Latency L0s <64ns, L1 <1us
                        ClockPM- Surprise- LLActRep- BwNot- ASPMOptComp+
                LnkCtl: ASPM Disabled; RCB 64 bytes, LnkDisable- CommClk-
                        ExtSynch- ClockPM- AutWidDis- BWInt- AutBWInt-
                LnkSta: Speed 2.5GT/s, Width x1
                        TrErr- Train- SlotClk- DLActive- BWMgmt- ABWMgmt-

Which surprised me, as I thought it was PCIe x8.

So I look up the tree for the bridge:

# lspci -s b5:00.0 -tv
-[0000:b2]---00.0-[b3-b6]----00.0-[b4-b6]----01.0-[b5]----00.0  Intel Corporation Battlemage G21 [Intel Graphics]

And, if I am reading it right (the tree and the bridge), it is really connected at 8GT/s with x8 width:

lspci -s b2:00.0 -vv
b2:00.0 PCI bridge: Intel Corporation Sky Lake-E PCI Express Root Port A (rev 07) (prog-if 00 [Normal decode])
        Subsystem: Super Micro Computer Inc Device 095e
        Physical Slot: 9
        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 36
        NUMA node: 0
        IOMMU group: 0
        Bus: primary=b2, secondary=b3, subordinate=b6, sec-latency=0
        I/O behind bridge: [disabled] [16-bit]
        Memory behind bridge: fa000000-fb3fffff [size=20M] [32-bit]
        Prefetchable memory behind bridge: 38f800000000-38fc007fffff [size=16392M] [32-bit]
        Secondary status: 66MHz- FastB2B- ParErr- DEVSEL=fast >TAbort- <TAbort- <MAbort- <SERR- <PERR-
        BridgeCtl: Parity+ SERR+ NoISA- VGA+ VGA16+ MAbort- >Reset- FastB2B-
                PriDiscTmr- SecDiscTmr- DiscTmrStat- DiscTmrSERREn-
        Capabilities: [40] Subsystem: Super Micro Computer Inc Device 095e
        Capabilities: [60] MSI: Enable+ Count=1/2 Maskable+ 64bit-
                Address: fee00038  Data: 0000
                Masking: 00000002  Pending: 00000000
        Capabilities: [90] Express (v2) Root Port (Slot+), IntMsgNum 0
                DevCap: MaxPayload 256 bytes, PhantFunc 0
                        ExtTag+ RBE+ TEE-IO-
                DevCtl: CorrErr- NonFatalErr- FatalErr+ UnsupReq-
                        RlxdOrd- ExtTag+ PhantFunc- AuxPwr- NoSnoop-
                        MaxPayload 256 bytes, MaxReadReq 128 bytes
                DevSta: CorrErr- NonFatalErr- FatalErr- UnsupReq- AuxPwr- TransPend-
                LnkCap: Port #9, Speed 8GT/s, Width x16, ASPM L1, Exit Latency L1 <16us
                        ClockPM- Surprise+ LLActRep+ BwNot+ ASPMOptComp+
                LnkCtl: ASPM Disabled; RCB 64 bytes, LnkDisable- CommClk+
                        ExtSynch- ClockPM- AutWidDis- BWInt+ AutBWInt+
                LnkSta: Speed 8GT/s, Width x8
                        TrErr- Train- SlotClk+ DLActive+ BWMgmt- ABWMgmt-

So I’m guessing that I am really getting x8 after all

Aljami25 · July 17, 2026, 11:19am

I’d test the RX 580 in another PC first. If the same thing happens, the card is probably the problem, not the motherboard.

Garrett_Kajmowicz · August 23, 2026, 2:05am

Would you be able to provide a link to more information about this? I’m seeing Gen 1.0 speeds on my Intel Arc A770 per lspci and I’m trying to figure out where the problem lies.

BillM · August 26, 2026, 4:44pm

Intel ARC reports the wrong speed, as I said in my post, look at the speed of the bridge to see what was really negotiated.

Garrett_Kajmowicz · August 30, 2026, 1:33pm

The link speed for the bridge was also showing PCIe gen 1.0 speeds. I did a firmware update and then started using the clpeak command to measure transfer rates. Between two I discovered I was indeed getting better-than-PCIe gen 1.0 speeds. I’m now fighting to get ReBAR enabled on the expansion slot which might have some minor performance gains. But a huge chain for PCIe switches isn’t helping.