[gameswithgo]

If you go with air cooling on a threadripper, I suggest going with a Noctua cooler instead of Dark Rock. Dark Rock extended the size of the heat plate to match the TR cpu size, but they didn't cover it with heat pipes, Noctua did. Cooling performance really suffers on the 3990X because there are chiplets on the edge of the cpu. the 32 and 24 core models it may not matter so much.

See: https://www.kitguru.net/components/cooling/luke-hill/threadr...

On non threadripper cpus I actually like Dark Rock better. Cooling is the same as Noctua but it looks cooler and was quieter for me.

[switchbak]

I went with the U14S for my 24 core TR, thinking I was crazy due to AMD's recommendation for robust water cooling.

I was worried at first when running heavy multicore benchmarks because the heat spiked so quickly. Turns out my workload scales quite poorly (boo), so I'm rarely pushing the temp envelope at all.

I did notice that a two fan setup on this was pretty noisy though, too much to bear sitting next to, so I threw it in the garage and ran some cables. Nice for summer temps and no AC in the house too!

I'm plenty happy with it now, even if the Noctua doesn't quite fit my case.

[paulmd]

water cooling isn't really that much more efficient than giant air coolers.

at the end of the day, dissipating heat is a function of the radiator fin area and air movement, the water is just a working fluid to move the heat to the radiator fins. Apart from having more thermal mass (takes longer to heat up/cool down) it isn't inherently more efficient than a heatpipe. It's water moving the heat either way, and in some ways the heatpipe is actually more efficient (evaporation moves more heat than raising the temperature of the water a few degrees).

People don't realize it, but a D15 (dual tower cooler, a bit bigger than your U12S) is about on par with a 240mm or 280mm AIO. A 120mm or 140mm AIO is worse than your U12S.

[m463]

I always thought water cooling was about noise.

You could move the heat to a giant radiator, which could have a giant fan. The bigger fan would move exponentially more air with exponentially less noise.

Meanwhile air cooling seems to require a lot more engineering, and you end up with something that looks like an oil refinery in the center of your motherboard.

[paulmd]

It comes down to how much surface area your cooler has (whether that's radiator or a cooler tower) and how much air is moving over it.

There is no magic about a water cooler that reduces noise. It is a thermodynamically determined process. The fin stack has a certain temperature, there is a certain amount of surface area, and a certain amount of air moving over it (at a certain temperature). A radiator really gives you no significant advantage in any of those areas. In fact a lot of radiators actually have less surface area than some of the really big air coolers like NH-D15. They are only maybe a couple centimeters thick, the D15 is about the same size as a 140mm cooler but the fins are four times as thick.

On top of that you have pump noise. An expensive custom loop with a nice quiet pump can reduce that significantly, but AIOs in particular are just never going to be quiet because of the pump. The "pump" on an air cooler is evaporation itself - the working fluid vaporizes on the coldplate (and cools it) and then condenses on the cooler part of the heatplate where the fins are cooling it. This is basically a "silent pump".

The best you can say about a radiator is that (a) by putting it on an intake you can guarantee that the air it's sucking is slightly cooler rather than being warmed by the ambient heat of the case, albeit with the downside that you are now pumping hot air over your other components, and (b) you can put the radiator in a more convenient location than sticking straight out of your motherboard.

(you can of course skip fans entirely! check out the HDPlex H5, it is a cool case where the entire thing is a heatsink, it uses heatpipes to move the heat to the chassis and the chassis itself is finned for dissipation. I have no imminent need for it but I lust for it anyway, it's just so damn cool. https://hdplex.com/hdplex-h5-fanless-computer-case.html )

[cjbprime]

Or for an even prettier one, Streacom DB4!

https://fabiensanglard.net/the_beautiful_machine/index.html

[Retric]

Your working from an overly simplistic model of cooling. The delta between the fin temperature and CPU temperature makes a huge difference in cooling efficiency. Two sets of fins may be moving the same amount of heat, but the CPU’s are at different temperatures due to differences in plumbing. Also, the way your working fluid flows through a radiator is a big deal, ideally you want the coldest part of the radiator on a return loop rather than heating the fluid as it’s passed to the CPU block.

Now, sure under ideal conditions and stock settings it’s not a big deal. But, in practice things get tricky.

[ben-schaaf]

This is only partially true. A larger radiator needs a faster/larger pump, leading to more pump noise.

Interestingly most air cooling solutions are really pump-less liquid cooling, as the liquid in the heat pipes is what transfers most of the heat away from the cpu.

[qes]

> Apart from having more thermal mass (takes longer to heat up/cool down)

_Much_ more thermal mass, and takes much longer to heat up and in most set ups will never reach the same temperature as the heatpipes in an air cooler - the waterblock will be cooler at idle and under load. I would think that larger temp delta allows heat to conduct away from the cpu package more quickly.

My 3960X sees 125MHz higher all core full load, almost 100MHz all core average work load, and 50MHz higher single core boost clocks under a custom loop (280+140 rads & Optimus TR3+ block) than under a Noctua NH-U14S TR4-SP3.

[derefr]

> at the end of the day, dissipating heat is a function of the radiator fin area and air movement, the water is just a working fluid to move the heat to the radiator fin

...in a fluid-recycling system (as all consumer PC cooling is.)

Water cooling is a lot more efficient than air cooling, in a fluid exchange system. Like if your HPC data-center is on the ocean, and you can just pump in cold ocean water, "spend" it by heating it up, and then pump the hot water to an outtake far-enough away that it's not heating up your intake water.

(An even-denser fluid would work even better, but we don't have oceans of even-denser fluids laying about.)

[m3at]

You're right, however one advantage of water cooling your cpu –especially for multi gpu builds that are common in ML setup– is that it moves the heat dissipation away from a crowded area.

[wincy]

Also consider the new Icegiant ProSiphon Elite [0]. Mine is arriving in September (due to Coronavirus related delays) but initial tests of prototypes by LTT [1] and others showed better cooling than AIO water cooling. Also since it uses dielectric fluid there’s no risk of leakage and frying your expensive computer. It’s $169 MSRP but based on what I’ve seen seems worth it. I’m not associated with them in any way just think it looks like a cool new product!

[0] https://www.icegiantcooling.com/

[1] https://m.youtube.com/watch?v=M13dWRL9qkc

[p1esk]

Yes, if it is as good as it seems, I don’t see any reason to use water cooling anymore.

[wincy]

One drawback of AIOs that I've read about is that you're no longer air cooling the VRMs surrounding the socket, which can decrease the life of your motherboard.

They also recently decided to include 4 120mm fans in the package, two push and two pull, which is a pretty crazy amount of air cooling.

[ADent]

If you believe their copy it won’t work on most computers in a tower case, since the CPU isn’t on the bottom and it uses a gravity feed to return the liquid.

[p1esk]

This used to be the main problem with this technology and they claim they solved it.

[fomine3]

Noctua's cooler is most nice look for me so there's no problem

[bob1029]

Noctua is an automatic default for me now. I've got the NH-U14S on my 2950X and a NH-D15 on my 1800X. Never have any problems with these. Easy to install and maintain. Will probably reuse both when I upgrade my CPUs.

[logjammin]

I think this is good advice in general -- you can't really ever go wrong with Noctua.

I built a Threadripper workstation last year but went with liquid cooling. However, I put 3 Noctua fans on the radiator and haven't looked back. Terrific company.

[trzeci]

My addition is that Dark Rock Pro TR4 is pretty bulky and I have a problem with Asus Zenith Extreme (Please note it's the older generation for 2950X) and radiator covers my PCIE#1 slot, so that I can't put graphics card there.

[fsociety]

Noctura is even more bulky, unless you get the slim version.

[keeganpoppen]

yep, i went with noctua w/ the dual fans in a push/pull configuration on a 3960x, and it's worked great so far. except that the two fans aren't quite the same color, sigh.

[bicknyers]

Also if you go air cooling and are confident with your abilities, consider delidding to drop temps. more (5 to 20C). If you go air cooling I would assume it is on the basis of long term stability, so don't use liquid metal either. Also invest in a nice PSU (gold minimum) with your peak load pulling only 75% of the rated max wattage

Edit: Like most things look at components real-world testing figures, in this case, wattage, as opposed to TDP when planning

[formerly_proven]

TR is a nine die CPU that is pretty difficult to delid and the improvement is minimal, nowhere near "5 to 20 C". It's not a 7700K.

[bicknyers]

Yeah to be fair I was basing my numbers on past projects namely Intel. I haven't looked at TR specifically just offered up the suggestion for those who have never heard of it to look into

[eightysixfour]

Ryzen CPUs are soldered, delidding has minimal impact.

[formerly_proven]

To be honest I can't recall any AMD CPUs that weren't soldered... apart from those that didn't have an IHS in the first place ;)

Intel was just like "we can save 4 $ BOM cost on a 500 $ part there" with their 4th-9th generation of CPUs. No thermal headroom? No problem.

[formercoder]

0.8%? Could be worth billions.

[bicknyers]

My mistake, I thought Ryzen CPUs were still bonded with silicone and a ??? grade paste on the IHS