Here is a sample of core usage on a 7950X3D / X670E / 32 DDR5 @6000 /4090, provided on another thread.
For context, monitor is 60 Hz at 4K. I don’t have the exact list of companion apps, but this is a power user, not vanilla MSFS.
This image was taken flying very low in a PG area, on GA aircraft, right after take off.
It’s kind of blurry, as it was taken with a phone.
Out of 16 cores we see 5 performance cores are nearly completely idle, 3 performance cores are between 17 and 41%.
The 8 Vcache cores are not all fully utilized.
This is just a sample, I am not saying it is enough to declare whether or not more than 8 cores is useful.
I’d be happy to see a similar snapshot showing a better utilization of the 16 cores in 7950X3D, so far I have not.