Is there anything for Ubuntu, how MSI AFTenberner for Windows?
Yes, there are lots of posts all over the internet about how to adjust OC settings in Linux, but there aren't any (I don't think?) graphical tools like Afterburner. You use the command line (see below), and once you figure things out, it's actually better than Afterburner. Everything based in percentages is really useless for sharing with others. For example, telling someone you set the power to 70% is useless without knowing what the TDP is for a particular card. However, telling someone the specific wattage setting + the card is better.
Here's what I use with my 6x Asus ROG Strix 1070s:
# These two lines allow me to run the rig 'headless' (without a monitor)
# Without them, the nvidia commands below won't run unless you log into the Ubuntu graphical UI.
export XAUTHORITY=/var/run/lightdm/root/:0
export DISPLAY=:0
# This enables power management
sudo nvidia-smi -pm 1
# This sets the desired power consumption to 115 watts (no percentages here; specificity!)
sudo nvidia-smi -pl 115
# this tweaks core and memory clock settings and sets the fan speed (ok, fan speed is a percentage...)
sudo nvidia-settings -a GPUPowerMizerMode=1 -a GPUGraphicsClockOffset[3]=200 -a GPUMemoryTransferRateOffset[3]=1050 -a GPUFanControlState=1 -a GPUTargetFanSpeed=25