Hi all,
I am having trouble with CPU Package C-states when having a GPU installed in the system. Without the GPU I am reaching C7 state with no problems while with the GPU installed the system is reaching C3 state only. My aim is to lower the idle system power consumption as much as possible while being able to use the GPU for Plex/Jellyfin video transcoding. I have tried running this script https://github.com/SpaceinvaderOne/nvidia_powersave, which is reducing the total power consumption of the system by putting the GPU in P8 state but still there is 15W difference of the GPU just being installed doing nothing and no GPU at all (also C3 vs C7 CPU state). Is there anything I can do to put the CPU in C7 state with the GPU installed (driver, settings, etc.) so I can lower the total system power consumption.
My system is:
MB: Asus Z370-P
CPU: Intel Core i7-8700K
RAM: 32GB
GPU: NVIDIA GTX1650
OS: TrueNAS Scale 25.04.2.5
The total system power difference is 25W without GPU vs 40W with GPU
GPU is installed in the second PCIe slot, the first slot is running an HBA with all my hard drives connected to it. And, no, the HBA alone is not preventing higher CPU C-states. I have verified that with just the HBA installed the CPU is reaching C7 state.
Powertop of the system with HBA and no GPU:
Powertop of the system with HBA and GPU:
Regards!