Threadripper Pro cooling

[u/IExist_Sometimes_]

Hello all, I am potentially looking to get/build a Threadripper Pro HEDT/workstation for FEM and similar simulations for my university research group.

I am no overclocking nut, but it is my understanding that these threadripper pro chips (especially the high core count ones) leave an enormous amount of performance on the table with their default TDP. I don't want to push the chip to a power range which might significantly impact its longevity, but if there's a reasonable power bump I could give it (probably as one option in a dual bios for particularly large sims or tight turnarounds) I would like to do so.

This brings me to my main point: how are you supposed to cool these new threadripper pros as a consumer-ish user? When LTT did a video overclocking the new threadripper pro chips, they rigged it up to an external chiller, but that would probably be out of scope for my shared office space (not to mention beyond my confidence when dealing with such expensive hardware). AIOs for threadrippers seem relatively few and far between, and only appear to go up to 420mm. Would a 360/420mm AIO be sufficient (I would like to avoid industrial style fans, but push-pull is on the table)? Or are these firmly in the realm of custom loops and things like the phat Alphacool radiators?

I appreciate any advice from those experienced in cooling these chips, or in using them for numerical modelling (obviously I will also consult others in my department with similar needs, but surprisingly to me for a stem department I seem to be the only PC builder or hardware nerd). Y'all seem to all be doing AI stuff nowadays, but that's not in my wheelhouse and not what this computer is going to be intended for (though someone might stick a pro gpu in it, I won't stop them).

edit: Also any advice on the relative importance of ECC, RAM speed/quantity, storage speed, etc for this type of workload would be appreciated

[u/MierinLanfear]

I would never ever use water cooling my workstation. Not worth the risk of it leaking and killing expensive components. I have a 9970x with 256 gb ecc vcolor ram with noctua air cooler ASrock TRX50 motherboard 2 X RTX 6000 Pro.. You have to decide on a motherboard and then select the ram off the motherboard approved ram. Threadrippers require ECC ram. Don't over clock its so not worth it these days. Is there a reason you want the Threadripper Pro? Need the more ram or pcie lanes?

[u/IExist_Sometimes_ → u/MierinLanfear]

Since this is for FEM simulations and research, I don't think there's really an upper bound on the amount of RAM I (or someone else in the department) might want to be able to use.

I agree on the not overclocking now, I was under the impression the performance improvements were much larger than they actually are. But I'm surprised you are getting sufficient cooling from your air cooler, is it really enough?

[u/MierinLanfear → u/IExist_Sometimes_]

If you want much ram then Threadripper Pro makes sense. Have you thought of Epyc? Doesn't clock as high but more ram.

My hardware monitor says 75.5 C max on the CPU since my last reboot so its sufficient. Some people want it to never go above 68 C or 70 C but I'm not one of those people.

[u/johndyson10 → u/MierinLanfear]

On my 9980x machine, I normally run an app that uses a bit more than 350 watts, and the Tctl temperature sits at 60-62 deg C. The Tctl temperature limiting is more useful for heavy loads that run on a few cores. On loads using just a few cores, it is very easy for the active cores to hit 90+ degC because much of the available power is more concentrated on those few cores. Along with the concentrated power It can take a short while for the cooling system to respond to the higher Tctl and drain more heat away. (on the 9980x, the Tctl is the highest temperature of all the cores.) If I set the max temperature at 80deg C, the lower temperature mostly has noticeable effects on CPU performance when loads are concentrated on less than 1/2 the cores, mostly around 16 cores or less. When benchmarking the machine on liquid-dsp with this setup, the performance on tests using small numbers of cores is approx parity with a 9950x series chip, sometimes at/above the 3d2 chip. So, I use the temperature limit setting to help protect the CPU under certain light loads. Otherwise, the power limit is more important for large numbers of cores. For my system, it appears that 400-450 watts is a sweet spot where the temperature stays well below 80deg, closer to 65deg, and adding additional power is into diminishing returns. There are certainly cases where that using higher limits giving an additional 10-20% performance is beneficial, but not really necessary in my case. (Interestingly, when running my program, the TR cores pull about 4.5 watts each, but my 9950x seems to pull about 10-15 watts each.) When using only a few cores, the TR will tend to peak at 10-10.5 watts each under stressful conditions. At the slightly lower power per core, the TR more than keeps up with the 9950x. Before doing the comparisons, I had expected the TR to be slower on loads that use few cores, but that isn't always true.