Cooling is probably one of the candidates of “all-things” field in any PC threads. It’s either the cooling or things will lead to cooling eventually. Overclocking on existing hardware obviously leads to cooling, and building a new PC from scratch also starts with some cooling in mind. Aesthetics, one that Apple fanboys are usually accused of, is obviously related to cooling. I think it is almost as a universally acknowledged truth that any computer-related communities will have cooling related threads.
With the new Mac Pro hinted, I hear people begging for water cooling Macs to be standard in the new Pro lines. I won’t deny the fact that they do have a point. It would give some breathing rooms for professional users during hardware intensive works. It would be more silent and smaller, and in fact, it is all-around win-win situation on specs sheet. These opinions usually conclude with what new Mac Pro must provide for “them” to stick around with Mac environment, except that it dully ignores one of the biggest hallmark of Mac ecosystem.
Water cooling denies any chance of customization, and I really mean “any customizations”. One of the biggest complaint against the current Mac Pro line was its soldered-in design. Not only that stopped any chance of upgrading RAM or SSD (Pro uses PCI-E SSD, which is nearly proprietary) and left its users with faulty AMD graphic cards. All of these could have been easily avoided, even put a stop to possible remediable measures without taking it to the Apple Store. Imagine if Apple had designed current trash can Macs with water cooling; we’d be seeing youtube videos of wet box opening, not cooked internals on twitter.
In fact, air cooling has remained industry standard for quite awhile now. Even data centers explicitly use air cooling, while, compared on specs chart, water cooling should be a no brainer. That is because of the industry practice; they’ve done risk-benefit analysis and it wasn’t worth it. To start things off, air cooling is no longer “let a fan handle it” practice. Countless studies have been done to improve form factors to account for the flow of airs inside the case, through each component, and the actual hardware is specifically designed and manufactured with that in mind. Apple may be making their own “hardwares”, but they are essentially no different from PC, just soldered in differently than commercially available ones. Unless one is genuinely arguing Mac Pro should return to the Power PC era, Apple will not be able to purchase or manufacture chips designed with water cooling in mind. An average consumer can convert his/her PC into a water cooling workstation, but only on one’s recognizance. That being said, water cooling hasn’t become an average consumer product yet because of its irreparable risk. Should any major PC manufacturer decides to go all-in on water cooling, that machine will have to be marked ‘water cooled’ all over the place, much like the featured image above. Otherwise it would be begging for mishap during maintenance.
Which brings me to the next point, Thunderbolt 3. Apple recently started supporting for eGPU through Thunderbolt with the release of High Sierra. Chances are Apple will push for further spread of Thunderbolts. It’s already a messy business to deal with one ATX sized PC, and it will further the burden of maintenance if you are dealing with one computer and several other, separately running, water cooled thunderbolt enclosures.* In theory, Apple could come up with a proprietary fix for this situation, by making the Mac to be the main pump which other enclosures can hook up to. Again the problem is the risk. To what point are we going to allow the users to regulate water right next to electronics? These aren’t exactly backyard irrigations we are talking about. And how often can we reasonably expect the users to pour in coolant? Without proper maintenance of pipes, tanks, filters, and pumps, water cooling simply doesn’t work.
*Thunderbolt enclosures provide PCI-E access, much like a severed motherboard. That being said, it will require its own cooling for separate power supply, card, and of course a separate pump and a tank, if it is a water cooled enclosure.
Now on the bright side, it is possible for Apple to adopt something like vapor chamber. Mac Pro’s trashcan design was primarily criticized for relying on one fan. Although the vapor chamber will not magically allow computers to run on one giant fan, it’s easy to imagine Apple adopting more solid cooling system that does not require constant maintenance. In fact, heat pipes are already used in laptop lines, covering most of the board with a couple of fans at most. But at this time, changing air with water and/or mineral oil doesn’t seem to add up.