It works fine for everything, but I figure I burned almost $10k on the machine (I got into a in for a penny in for a pound mode for some stupid reason), if I can get more performance, less energy use, and lower temperatures for only ~$700 more, it would be worth it. Then I would recycle the 7950X3D into one of my older computer frames with some lower end components and then I would have a workstation to run some secondary tasks on. I have been wanting to learn how to render, but never felt comfortable tying my main computer with it and my older computers are much less capable.
Similar stories here: there is usually some machine in the family that could do with an upgrade and it results in a domino upgrade cascade and an opportunity for daddy to try something new which might not make sense in a straight swap.
For me it was upgrading my biggest workstation from a 5950X to a 7950X3D, while the former became the secondary, whose 5800X3D went to a kid's gamer rig, replacing an i7-7700k etc.
But using CPU power for rendering doesn't really make any sense any more, because e.g. Blender will work much faster with an RTX GPU than any CPU you can throw at it. It was nearly identical between a Xeon E5-2696 v3 and an RTX 2080ti some years ago, but these days even an RTX 4070 will outpace the 7950X3D, while the RTX 4090 it hosts makes it look like a lame old dog.
Apart from large compile jobs and running lots of nested VMs for my lab experiments there are really not that many use cases for a big CPU like the 7950X3D. In the mean-time, I'm just glad I got a rather good productivity chip that is more than half decent even at the occasional gaming when the latter doesn't pay the rent.
The flexibility is worth the relatively modest estra money, compared to the total amount of money in those boxes, where RAM, NVMe storage and GPUs figure much bigger.
With the 5950X using DDR4-3200 (ECC) and the RTX 4090 the occasional game didn't manage to hit the sweet spot between 60 and the 144 Hz my 4k 42" monitor supports, and that's where the 7950X3D manges to do quite a bit better with DDR5-6000 (ECC). For the home-lab use I need reliability so it's ECC on the RAM and no overclocking beyond PBO on the CPU, which unfortunately meant going from 128GB in four DIMMs on the 5950X to 96GB in just two DIMMs on the 7950X3D.
Again, not really an issue, but I'd have paid extra for the flexibility of using 128 or even 192GB: some experiments just take a lot of RAM, even if most of the time it's unused but ready to jump in.
I actually don't think a 9950X3D will deliver a noticeable improvement on any use case I am currently running, because with my reflexes there is no benefit in running games at 200 FPS or better, nor am I running circuit design or HPC workloads. Nor do I think I'll be able to do meaningful things with a 128 core CPU, while 10, 40 or even 100GHz might still hold attraction, if it could be done.
So for the foreseeable future, I might have reached the summit of what I'll need before my ultimate retirement, unless some gene engineering moves that horizon significantly.
But another downstream event might trigger the next cascade and that might have me replace the 7950X3D with a 9000 or Zen 6 anyway.