On a whim I just experimented with a few more things:

1) Disabling AVX512F ([c]CpuSupportsAVX512F=0[/c]) didn't make any noticeable difference

2) Running 4x4 workers instead of 2x8 made a significant difference... the wrong way: nearly locked up the machine, took me 30 seconds to be able to exit Prime95.

Running 2 workers on AMD 2 chiplet CPU's is more preferable. Yes.
From hwinfo64, I was curious about the RAM bandwidth that is used.

System can be laggy and unresponsible if RAM memory controller is overwhelmed and keeps getting bottlenecked.
When I was running 2 PRP at the same time, my PC was veryyy slugish, so now I work only 1 PRP + 1 DC for my 5900X.

Unless you can set limitation for max used RAM bandwidth, leaving some of it for normal usage, then large P-1 will consume all the resources. I am talking about bandwidth, not the size.

I attached my screenshot with DDR4 3800 running PRP. When it write/reads at the same time, its a heavy task for RAM and Memory controller.

Edit: 7950X is very fast CPU, with a lot of cores. It can easily overwhelm memory controller, especially with 64 GB of ram.

I added additional screenshot.

Now I have 2x6 setup, I have 12 cores for 5900X.
1st worker does DC at FFT 3360
2nd worker does PRP at FFT 6M

In this setup, it is close to running max bandwidth for RAM, but I have enough responsiveness to not be bothered while doing any other task - working on documents, browsing, discord, movies etc.

If I want to do something heavier or play some games, have to turn p95 off completely thou.

My suggestion - try to run only 1 P-1 worker, other worker on something lighter.

I've given up running P-1 for the last several months, I run 2x PRP/DC workers. It still lags. It's more usable running only 6 (instead of 8) threads per worker, but it's still noticeable.

Firing up HWiNFO, I see running 2x6-core LL I have RAM read/write of 27/18Gbps.
With 2x8-LL it's 30/19.
2x8 P-1 stage 2 it's 38/27.

I see, not sure what else I could suggest.
Running 2x6 is not the worst option to be honest. Especially if it is LL + PRP or P-1.

I assume 38/27 RAM bandwidth is the hard cap already for 2x8 P-1, so keeping at ~30/20 may leave enough leftover bandwidth to keep your system responsive.

Can go deep dive in RAM overclocking and tuning, to gain out more performance out of it, up to 5-10%.
But it requires time and dedication to learn the nuances of RAM overclocking.

Here is an youtube video of recognized overclocker introducing primary overclocking of ram for AMD 7000 - [url]https://youtu.be/dlYxmRcdLVw[/url]

I don't really want to push my RAM much further, it's already "factory overclocked" with the EXPO profile and runs warm (66C) and even if I could get another 10% bandwidth I don't think it would really fix the underlying issue. I'll just make do with fewer workers during the daytime.

Gotcha, 66c is quite warm, I would look for a way to improve case airflow to bring it a bit down, either with fan on top of them (picture added) or modifying the heat spreaders. High temps can cause some instability, but its not a big deal if error checking does not get triggered and probably would not help with current performance.

I am out of ideas what to suggest further to run it at full speed with good responsiveness. If you find out anything, would be good to know. Good luck!