Why do people pay so much extra for liquid-cooled computers when fans seem to do the same thing?
It’s because liquid has a better heat transfer coefficient (ability to absorb/dissipate heat) than the classic metal/fan combo, for everyday use u won’t notice a subtle difference but things gets wild when u are doing something “hard” like gamming/video editing for example.
Basically, because fans aren’t as good.
Liquid cooling can cope with higher temperatures and cool components down more quickly.
For PCs being used for light tasks like web browsing or word processing, a fan can manage fine. Computers being used for computationally strenuous things – like gaming, CAD/graphical work, crypto mining or similar produce far more heat than a fan can deal with.
Think of it this way – if you were too hot, what would cool you down more: blowing a fan on you, or immersing yourself in a swimming pool? How hot would you need to be until the fan wasn’t good enough, and only the pool would do?
Those talking about liquid’s heat capacity are wrong, at the end of the day you have to use a radiator and fans to get the heat into the outside air.
But you can use a bigger radiator with slower moving fans for quiet operation or high speed fans for peak performance
A heatsink is really only as good as its surface area. A traditional tower cooler really maxes out around the size of an [NH-D15](https://noctua.at/en/nh-d15) with two big towers and a pair of 140mm fans. That’s about as large and heavy of a standard heatsink as you can mount in most cases, but its *biggg*
The little all in one liquid coolers are significantly smaller on the motherboard since its just a pump and the contact area, and feed into a separate radiator that can be mounted elsewhere. They seem to come up to 360mm (3x120mm fans in a line) and will perform inline with a big air cooler like the NH-D15 being about as loud and about as cool
Big custom liquid cooling loops are a different story though since you can mount multiple radiators. The CPU feeding a 120x360mm radiator might be about equivalent but having the CPU and GPU hooked up to 2 120x480mm radiators(8 total fans) will give significantly better cooling and/or than just 2 on the CPU and 3 on the GPU trying their bestest in their limited space
The real answer is that fans were not very profitable parts for a while until companies like Corsair made a killing on all-in-one liquid coolers. They saw significant development, despite some patent obstacles, which made them leapfrog air cooling for a good bit. They had more room to seem “premium” and every computer needed one, but only one. Why sell a $15 cooler for $25 when you can sell a $50 cooler for $100?
In 2023, air coolers are basically neck and neck with liquid cooling in almost all scenarios, barring outliers.
Also of note, cooling is facing new challenges every year. With AMD in the lead, cooling small chiplets with a small surface area became more important, and although wattage is plateauing a bit (unless you use Intel where it has quadrupled) it is still higher than it used to be.
The one unique advantage that industrial water cooling has over air is a much better ability to transport heat, even if you aren’t doing that much different volume. You can pump water outside of your “system” to be expended in other ways. For instance, heating the building! Moving air long distances like that is inefficient.
Liquid cooling has greater thermal mass and cooling capacity, if done proper. Good air cooling can definitely compete with weaker liquid cooling, but liquid cooling does have its benefits. The heat capacity of water means it can take away heat quick and the thermal mass means it takes longer to increase in temperature meaning the cooling side doesn’t have to kick in that quickly and that often.