2070 Super CPU settings

[MeeLee]

For anyone interested,
I run 2 servers, and when swapping my 2070 Super from one to another, I found a ~10% drop in performance (1.35M PPD), which I couldn't figure out why (until today),

I disabled Intel Turbo Boost on most of my PCs, and the 2070 was running on a 6 core 2,9Ghz CPU. It saves me a few watts.
HTOP indicated that not only the 2070 Super, but the 2080 on that server also was showing 100% of CPU utilization (aside from the zero data Nvidia sends).
I increased the base frequency from 2,9 to 3,2Ghz (with turbo on the CPU goes to 3,9Ghz), and the super was getting ~1,5M PPD again.
HTOP indicated ~90-95% cpu utilization.

That means a modern +3Ghz CPU is needed for RTX 2070Super/2080 and up.
2,9Ghz worked well with a standard RTX 2070, 2060 or below.
the increase in CPU frequency did not affect the 2070 and 2060 running on that same server (meaning, if you're running a (few) RTX 2060/2070 GPUs on a CPU that's over 3Ghz, you'll just waste more watts).

I also disabled CPU cores I did no longer need.
Linux doesn't require 1 CPU thread for the OS, so I am running only the amount of cores that are feeding GPUs.

The drop in performance from running 3 GPUs with 4 CPU cores, to running 3GPUs with 3CPU cores in linux measures about 1,5 to 2%.
The benefit, aside from saving a few watts, is that the same CPU cores will be utilized, and the data doesn't get shuffled around the CPU (causing CPU cores to continuously shift between threads and passive, and heat and cool all the time.

[bruce]

Are you sure you're comparing performance on the same project? There can be major differences depending on the project you're assigned.

[MeeLee]

No, average performance over several projects.
The other server running RTX 2060 GPUs, I dialed down from 3Ghz to 2.9Ghz on the CPU, without any noticeable performance loss, however there also was no noticeable reduction in Watts <6 Watts on 300 = <2%.

[Nathan_P]

what cpu?

[MeeLee]

I run mostly Intel CPUs
I3 9100F
I5 9400F
I5 7400
Pentium Gold G5600
Celeron G4900