With the size of air-coolers these days, and how they all have integrated heat pipes, I'm beginning to wonder if we've crossed the distinction barrier with liquid-coolers.
Air cooling is wonderful. I didn't watch this video but I use a giant Noctua heatsink on my system (Intel 6950X, not quite as demanding as Threadripper but hardly a cold-running CPU) and I have zero regrets. I have used all-in-one watercoolers, and ... they just die after a few years. I have owned three and all three of them died in less than 2 years each. Each time, I very sadly woke up in the morning with the realization that I'm not going to be using my computer today. AIOs have not, in my experience, been quieter or yielded better temps than air cooling. So I am not sure it's worth it.
Obviously a homebuilt watercooling rig is going to be way better than AIOs, but it requires extensive maintenance. It's water. Stuff will grow in there. It evaporates. Joints loosen over time and could end up shooting water all over your $6000 workstation.
To me, it's not worth it. Threadripper requires a big heatsink. So be it.
Linus Tech Tips did a video in which they were unable to beat a high-end air cooled nuctua set-up with any sort of water cooling solution. And by unable to beat, I mean both temp-wise and sound-wise. Maybe, just maybe, you might be able to beat air cooling on one dimension with a very expensive custom loop, but it's totally not worth it.
Those air cooled units with the heat pipes are effectively heat pumps, and heat pumps are crazy efficient at cooling. They rely on evaporative cooling, which soaks up substantially more energy, so much so that it's possible to to get temperatures noticeably below ambient using the method.
Converting water to steam takes about (from the top of my head) 5x more energy than it takes to increase it by one degree. I imagine the coolant used in these heat sinks is at least this efficient, if not more, and is something that evaporates well below 100°C.
If heat sinks were like using cars and roads to transport people. A water cooled setup would be like expanding the size of the roads to increase the number of cars that can transport people. While those heat pipe coolers are like replacing cars with trains, so you can do a lot more the same amount of space.
> Converting water to steam takes about (from the top of my head) 5x more energy than it takes to increase it by one degree.
I think this greatly underestimates the potential of evaporative cooling. The "specific heat of water" is 1 calorie/gram °C --- that is, one calorie can heat one gram of water by one degree Celsius if no phase change is involved. The "heat of vaporization of water" is more than 500 calorie/gram at 100°C. That is, the energy necessary to convert a given quantity of liquid water from just below boiling to steam is not 5x the energy necessary to raise that amount of water 1°C, but 500x! You are probably remembering that this is 5x the energy necessary to take liquid water all the way from 0°C (almost frozen) to 100°C (almost boiling).
My experience is the opposite. I'm sure all in one water cooling varies, but water cooling can be done mostly with cheap parts from a hardware store. The most exotic part is the water block, followed by the pump. Radiators can be used, but a lot of computers can probably cooled by using soft copper spools and a 200mm fan.
The pump does not need to have air flow to do its job and airflow is what carries noise. The water just has to be able to flow through the loop, pretty much any rate of flow will be pushing enough water to move heat away. If you hold your hand to a water block with the pump turned off, let it warm up and turn it on, it feels like the water is going over your hand. The temperature change is immediate. If you turn off the pump while the CPU is running, the temperature will rise a few degrees each second. Once the pump goes on the temperature drops down immediately.
There is no reason that the liquid should evaporate unless there are leaks and joints don't necessarily loosen over time. Also leaks are unlikely to manifest in something bursting and water spraying, even if you had enough pressure from your pump, which you don't (a pump can probably only pump water four or five feet higher than the pump itself, even if it is more powerful than the loop needs).
I have never had to maintain or fix something after it is together. Use vinyl tubing from the hardware store over the barbs and use small pipe clamps on top of them.
Yeah ultimately the benefit of water cooling is just to route the heat to where you have room for a bigger radiator. If you squish a big enough radiator on top of the cpu and have good airflow through the case there, you can generally get about the same cooling performance as most sane liquid cooling solutions.
To be fair, not all air-coolers are of that size. Person who built the computer is probably overdoing most of the things, including the cooling, even if you're running it constantly.
But also depends on where in the world you live and what the climate is like.
That isn't overkill size for a 24 core cpu. However that particular heat sink is not great on threadrippers. It is probably ok for the 24 core TR because it doesn't have chiplets on the edges. The DarkRock TR model doesn't have heat pipes on the edge of the heat plate. They just made the heat plate wider, and it suffers on the 3990x for it. The Noctua equivalent is a better choice for these cpus.
For the normal desktop cpus, I like the Dark Rock better. Cooling is the same as noctua but was quieter for me.
Yeah I actually stopped doing water cooling (usually Corsair AIOs) this year and went with this HSF just for ease of complexity, not that I ever had any problems with my AIOs.
I should note it's WAY louder than I thought it'd be and it's made getting to my NVME drives a bit difficult.
I didn't do much research beyond "best analog HSF vs watercoolers" and when it showed up I couldn't believe how big it was.
I went from AIO to air cooling quite recently after the pump on my AIO failed. Honestly not sure if I was just going from a bad AIO to a good cooler (smaller version of the Dark Rock Pro) but I actually found it to be quieter and the performance difference.
Honestly the best bit though was the piece of mind that I don't have liquid inside my computer anymore. The idea of the pump leaking down onto my GPUs when I'm not around was stressful.
It does seem like watercooling might be a better option for these high-TDP CPUs. I went back to air cooling on my latest build because I went with a Ryzen 3600 which only puts out around 65W under load. IMO, the cost/benefit of watercooling just isn't there for normal use cases because of the risk of leakage.
Building an open water loop would be awesome for the GPU cooling. I just can't justify the expense.
Liquid cooling excels in flattening temperature spikes, usually from bursting CPU frequencies, since it has more thermal mass and can absorb spikes without much change in coolant temperature.
Air cooling excels mostly everywhere else.
Neither can cool your system to below ambient room temperature.
The AIO are not really worth it.
Custom loops can be if you do it right.
My basic rule is - There is no replacement for displacement. get a big, like proper big 200mm(in both directions) or bigger radiator and a single big fan.
Ultimately, you want more surface area to blow air across to cool things. "Water cooling" is really "water transports heat to fins for cooling". Just a bigger version of the heatpipe really.
If the fins are not better suited to airflow cooling then it won't help you.
The AIO radiators don't add that much more fin area than a good air cooler if at all. But you can put them somewhere outside the otherwise warm case if that helps. Maybe if you live some cold and your desk is just right you could dangle it out the window?
Also, for the noise conscious, two(often on the 280 AIOs) or more fans "beat frequency" is a thing. Also why I don't like "push-pull" configs on air coolers.
Obviously a homebuilt watercooling rig is going to be way better than AIOs, but it requires extensive maintenance. It's water. Stuff will grow in there. It evaporates. Joints loosen over time and could end up shooting water all over your $6000 workstation.
To me, it's not worth it. Threadripper requires a big heatsink. So be it.