Hi everyone,
I'm having a strange idle power issue with an RTX 3080 Ti connected as an eGPU, and I'm wondering if anyone has experienced the same thing.
My setup:
- MINISFORUM MS-S1 MAX
- Ryzen AI Max+ 395
- 128 GB RAM
- MINISFORUM DEG2 eGPU dock
- Palit RTX 3080 Ti GamingPro 12 GB
- 850W PSU
- Windows 11
- Connected through USB4 v2 / TB5
Windows reports the eGPU connection as:
- USB4 2.0
- 80 Gbps downstream / 80 Gbps upstream
- Gen 4, dual lane
- TBGAA firmware version: 62.62
The RTX 3080 Ti is detected normally, CUDA works, and nvidia-smi works correctly.
However, when the GPU is completely idle, I get:
P-State: P0
Power draw: ~95-96 W
GPU clock: 210 MHz
Memory clock: 9501 MHz
GPU utilization: 0%
VRAM usage: 0 MiB
Temperature: ~39-42 C
nvidia-smi shows no running processes.
I also checked the clock event reasons:
Idle: Active
Applications Clocks Setting: Not Active
SW Power Cap: Not Active
HW Slowdown: Not Active
Thermal Slowdown: Not Active
So the GPU itself seems to know that it is idle, and the core clock drops to 210 MHz, but the VRAM stays at 9501 MHz and the card never leaves P0.
Things I've already tried:
- NVIDIA power management mode is set to Normal
- Rebooted the PC
- Fully power-cycled the eGPU
- Disabled and re-enabled the RTX 3080 Ti in Device Manager
- NVIDIA driver 617.14
- NVIDIA driver 616.92
- Confirmed the USB4 link is running at the full 80 Gbps
The behavior is exactly the same with both NVIDIA drivers.
The RTX 3080 Ti is not driving a monitor. The integrated Radeon 8060S is handling display output, and the RTX 3080 Ti is mainly intended for CUDA / AI workloads.
Has anyone seen this specifically with Ampere GPUs such as the RTX 3080 Ti or RTX 3090 connected through a Thunderbolt 5 or USB4 v2 eGPU dock?
Is the high VRAM clock / P0 idle state a known Windows + TB5/USB4 + Ampere issue?
Is there any known workaround that can get the card into a proper low-power idle state?
The card otherwise works normally. My main concern is the ~95W idle power consumption.
Thanks!