Thank you
@serverpanda and
@topmysteries5 for the information and advice you gave me.
I know that Ryzen 3000 are very capable cpus with an almost unbeatable price/performance ratio. They are not for me, though. Indeed, I'm building my next deep learning platform: I need more than 16 lanes (the bare minimum are 3 slots at 8x each for the GPUs, the taichi is good since its 16x/16x/8x layout), and 128gb of ram, preferably ECC.
But most of all, I need support for Intel MKL, which the amd cpus do lack. The best option for me would be a Xeon Gold/Platinum, for which I found many QS samples at good prices on ebay, with a core count between 16 and 22. However, I cannot manage to find a single-socket lga3647 board with enough 16x slots...
In my experience
@topmysteries5, the Xeons E5 do consume way less power than their nominal TDP. My E5-2680v2 (10c/20t, 115W) tops at ~90W under prime95 at 3.1ghz (all cores). If I disable turbo, it drops to ~60/65W @2.8Ghz, measured with coretemp. I do expect however, that the actual power draw won't scale linearly with frequency. I do expect the -97v3 to scratch 200W when modded, which maybe will require liquid, or at least an air cooler so good it would cost almost as a liquid.
One option to stay cool would be the 2660v3. It has 10 cores with a base freq of 2.6 ghz. Max turbo 2.9Ghz on all cores, that would become 3.3 Ghz with the mod. Ten haswell cores at 3.3 won't be bad, and since the cpu has a TDP of 105W, I don't expect it to draw more than ~120W as modded. In any case, I'll be fine with the cooler I always use with 2011 processors, the CM Hyper 412R (20$).
The next option would be the 2690v3 (12C, 2.6,3.1,3.6 respectively base, turbo on al cores, turbo modded). It's a 135W cpu, I dunno if I'll be ok with the air cooler.
As a footnote, I find the performances of Ryzen 3000 to be a bit too good to be true... Look:
The 2697v3 has almost twice the cores of the 3700x, and even the mighty W-2155 is beaten, no matter being latest intel generation and with 10 cores..
Don't know, it stinks a bit..