GPU config for etherium mining on Ubuntu 20.04

# References
# https://u2pia.medium.com/ubuntu-20-04-nvidia-gpu-control-through-ssh-terminal-bb136f447e11
# https://unix.stackexchange.com/questions/367584/how-to-adjust-nvidia-gpu-fan-speed-on-a-headless-node

# This gist is for GPU configuration for mining on Ubuntu 20.04
# This worked with dual GPU machine (GTX1070/RTX3070).

# Set coolbits which enables to control all gpu fan/clock via command line
sudo nvidia-xconfig -a --cool-bits=28

# Edit xorg.conf.d/10-nvidia-.conf
sudo vi /usr/share/X11/xorg.conf.d/10-nvidia.conf
# Edit like below
```
Section "OutputClass"     
  Identifier "nvidia"     
  MatchDriver "nvidia-drm"     
  Driver "nvidia"     
  Option "AllowEmptyInitialConfiguration" 
  Option "Coolbits" "28"    # <-- ADD THIS LINE
  ModulePath "/usr/lib/x86_64-linux-gnu/nvidia/xorg" 
EndSection
```

# Reboot
sudo shutdown -r now

### After reboot ###

# Search for Xauthority
sudo ls -AFlh /run/user/$(id -u gdm)/gdm/
# If you find `Xauthority*` file, then you can control gpu fan/clocks

# Set config options
sudo DISPLAY=:0 XAUTHORITY=/run/user/$(id -u gdm)/gdm/Xauthority nvidia-settings \
--assign [gpu:0]/GPUFanControlState=1 \
--assign [gpu:1]/GPUFanControlState=1 \
--assign [fan:0]/GPUTargetFanSpeed=80 \
--assign [fan:1]/GPUTargetFanSpeed=60 \
--assign [gpu:0]/GPUGraphicsClockOffsetAllPerformanceLevels=-200 \
--assign [gpu:0]/GPUMemoryTransferRateOffsetAllPerformanceLevels=250
--assign [gpu:1]/GPUGraphicsClockOffsetAllPerformanceLevels=-130 \
--assign [gpu:1]/GPUMemoryTransferRateOffsetAllPerformanceLevels=900

# Enable power limit configuration
sudo nvidia-smi -pm 1
# This sets pl to 120W
sudo nvidia-smi -i 0 -pl 115
sudo nvidia-smi -i 1 -pl 130

# Monitor gpu temperature
nvidia-smi