Full disclosure: I got a 1950x based machine last autumn/fall, and am something of an AMD fanboy since.

Linus Torvalds (torvalds.delete@this.linux-foundation.org) on August 13, 2018 3:48 pm wrote:

[...]
> I'm seriously considering
> upgrading to an AMD system, and the new threadrippers would really fit my load.
>
> During the merge window (like now), I spend a fair amount of time double-checking
> my merges by doing builds before pushing out, and my old i7-6700K is showing
> its age, with the kernel having grown, and meltdown slowing things down.
>

My lens was through rendering algorithms / image synthesis. From that point of view it is IMHO clearly visible that the new 32 core model is seriously starved for memory bandwidth.

"Old style" renderers like PoV-Ray scale very well. Textures are procedural, and secondary rays are being shot in fairly low number, with quite a bit of locality. Memory bandwidth or latency is not much of a problem. Performance gain from 16 to 32 cores is somewhere around 70%.

Blender, in contrast, is a contemporary production quality renderer, but usually spares the effort of a full simulation of light physics. Textures are photogrammetric maps, and some effects may spawn many secondary rays. Blender still scales from 16 to 32 cores, but you gain maybe 30% to 40%.

Very modern physically based path tracers randomly sample all of the scene with little locality, and also use high resolution high precision textures. Scaling from 16 to 32 cores can yield as little as 15% to 20% speedup.

So the 32 core model is not an upgrade I would consider, even if I could spare such money on a whim.

> My main worry is noise. I'm not sure I want to deal with the blower required for a 180W+ CPU.
>

I can attest that Noctua's U14S tower cooler keeps the 1950x under 60 degree Celsius in a well ventilated case. It's not silent, but quiet enough that I can fall asleep in that same room. That cooler is an overpriced, overengineered marvel of perfectionism - I love it! :-)