Hello, are there any troubleshooting reccomendations given the following history: The Intel Arc Pro B60 GPU installed in the Beelink EX Pro Dock is completely invisible to the operating system despite:
✅ GPU fans spinning (confirming power delivery is working)
✅ Dock power light illuminated
✅ Thunderbolt controllers authorized in Linux
❌ No PCIe device enumeration behind Thunderbolt ports
❌ No GPU detected in lspci or vulkaninfo
- SYSTEM SPECIFICATIONS
Component Specification
Host PC Beelink GTi15 Ultra
CPU Intel Core Ultra 9 285H (Arrow Lake-P)
iGPU Intel Graphics [8086:7d51]
Thunderbolt Controller Meteor Lake-P Thunderbolt 4 [8086:7ec2/7ec3]
BIOS Version GTi15T204 (01/13/2026)
Operating System Ubuntu 24.04.4 LTS
Kernels Tested 6.17.0-19-generic (Ubuntu Stock), 6.19.10 (Vanilla)
GPU Sparkle Intel Arc Pro B60 24GB (SBP60W-24G)
Dock Beelink EX Pro Docking Station (600W PSU)
Power Connection 1× 8-pin PCIe from Dock to GPU
- CRITICAL ERROR LOGS
A. Thunderbolt Communication Failure (Primary Evidence)
[ 2228.342514] synth uevent: /devices/pci0000:00/0000:00:0d.2/domain0/0-0: unknown uevent action string
[ 2228.342520] thunderbolt 0-0: uevent: failed to send synthetic uevent: -22
[ 2228.348669] synth uevent: /devices/pci0000:00/0000:00:0d.3/domain1/1-0: unknown uevent action string
[ 2228.348672] thunderbolt 1-0: uevent: failed to send synthetic uevent: -22
Analysis: Error -22 (EINVAL - Invalid Argument) indicates the Thunderbolt kernel driver cannot communicate with the dock’s internal controller. This is a firmware/handshake failure.
B. PCIe Link Training Failure
[ 0.373616] pci 0000:00:01.0: broken device, retraining non-functional downstream link at 2.5GT/s
[ 1.373872] pci 0000:00:01.0: retraining failed
Analysis: PCIe link training failures on the platform indicate potential signal integrity issues.
C. Thunderbolt Port Status (No Devices Enumerated)
$ lspci -vvv -s 00:07.0 -t
-[0000:00]—07.0-[04-2d]–
Analysis: Thunderbolt Root Port #0 exists but the subtree [04-2d] is empty. No devices detected behind the port.
D. Thunderbolt Authorization Status
$ cat /sys/bus/thunderbolt/devices/0-0/authorized
1
$ cat /sys/bus/thunderbolt/devices/1-0/authorized
1
$ cat /sys/bus/thunderbolt/devices/0-0/device_name
Gen14
$ cat /sys/bus/thunderbolt/devices/1-0/device_name
Gen14
Analysis: Thunderbolt domains show host controllers only (Gen14 = Meteor Lake). No dock devices appear.
- DIAGNOSTIC COMMAND RESULTS
A. GPU Detection (FAILED)
$ lspci -nn | grep -i arc
(empty output - no GPU detected)
B. Vulkan Devices (FAILED)
$ vulkaninfo | grep “GPU id”
GPU id = 0 (Intel® Graphics (ARL)) <– iGPU only
GPU id = 1 (llvmpipe (LLVM 20.1.8, 256 bits)) <– Software renderer
Arc Pro B60 is NOT listed.
C. PCIe Link Status (FAILED)
$ lspci -vvv -s 00:07.0 | grep -E “LnkSta|LnkCap”
(empty output - no link established)
D. Thunderbolt Domain Devices (FAILED)
$ find /sys/bus/thunderbolt/devices/0-0/ -type d
/sys/bus/thunderbolt/devices/0-0/
/sys/bus/thunderbolt/devices/0-0/wakeup
/sys/bus/thunderbolt/devices/0-0/power
/sys/bus/thunderbolt/devices/0-0/usb4_port3
/sys/bus/thunderbolt/devices/0-0/usb4_port3/power
/sys/bus/thunderbolt/devices/0-0/usb4_port1
/sys/bus/thunderbolt/devices/0-0/usb4_port1/power
Analysis: USB4 ports exist but contain no child devices. The dock is not enumerating.
E. Thunderbolt NHI Controller Status (WORKING)
$ lspci -vvv -s 00:0d.2
00:0d.2 USB controller: Intel Corporation Meteor Lake-P Thunderbolt 4 NHI #0
Control: I/O+ Mem+ BusMaster+
Kernel driver in use: thunderbolt
Analysis: Host Thunderbolt controller is active and driver loaded correctly.
TROUBLESHOOTING STEPS COMPLETED
Step Result
Kernel 6.19.10 (Vanilla) ❌ GPU not detected
Kernel 6.17.0-19-generic (Ubuntu Stock) ❌ GPU not detected
Enable BusMaster on TB ports ✅ Enabled, no change
PCIe bus rescan ❌ No new devices
Thunderbolt re-authorization ❌ Invalid argument error
Force Thunderbolt power control “on” ❌ No change
Full power drain (60 seconds) ❌ No change
Cold boot sequence (Dock ON → PC ON) ❌ No change
BIOS: Above 4G Decoding = Enabled ✅ Verified
BIOS: Re-Size BAR = Enabled ✅ Verified
BIOS: Secure Boot = Disabled ✅ Verified
HARDWARE VERIFICATION
Check Status
GPU power (fans spinning) ✅ Working
Dock power light ✅ On
8-pin PCIe cable connected ✅ Verified
GPU seated in dock slot ✅ Verified
Proprietary cable connection ⚠️ Cannot verify signal integrity
PCIe Topology Analysis (lspci -vvv):
Thunderbolt Root Port 00:07.0 is configured with a 32GB prefetchable memory window (5810000000-600fffffff), indicating the BIOS/UEFI has correctly allocated resources for an external GPU.
Bus Enumeration Gap: The bridge expects devices on bus range 04-2d. However, no devices are enumerated in this range. The PCIe bus scan skips directly from the Thunderbolt root ports to internal devices (00:0a.0).
Link Status: No LnkSta (Link Status) is reported for the Thunderbolt ports, confirming that no physical PCIe link has been established with the dock.
Host Controller Status: The Thunderbolt NHI (00:0d.2) is active and bound to the thunderbolt driver, proving the host controller is functional.
Conclusion: The failure is at the physical layer (PHY) or firmware handshake. The dock’s internal PCIe switch is failing to train the link or respond to the host’s enumeration requests. This is consistent with a defective proprietary cable, a dock firmware bug incompatible with Arrow Lake-P, or a hardware fault in the dock’s PCIe switch.
The Host Interface (NHI) is Active
Look at 00:0d.2 and 00:0d.3:
00:0d.2 USB controller: Intel Corporation Meteor Lake-P Thunderbolt 4 NHI #0
Kernel driver in use: thunderbolt
Region 0: Memory at 6028240000 (64-bit, non-prefetchable) [size=256K]
Analysis: The Thunderbolt Host Controller is loaded, has memory mapped, and the thunderbolt driver is active.
Implication: The CPU is ready to talk to the dock. The failure is not in the CPU's Thunderbolt controller.
The “Missing” GPU
Expected: You should see a device like 04:00.0 or similar (depending on the dock’s internal switch) with VGA compatible controller or PCI bridge.
Reality: The scan jumps from 00:07.3 (Port 3) directly to 00:0a.0 (Signal Processing). There is a complete gap in the bus enumeration.
PCIe Link Status is Missing
Notice that unlike the working NVMe (03:00.0) or WiFi (ad:00.0) which show LnkSta (Link Status) details, the Thunderbolt ports (00:07.x) do not show LnkSta in this output because no device is connected to negotiate a link speed.
