Big annoyance with SFF builds is noise. Many of these are overall smaller than just my GPU and CPU cooler, and SFX PSUs have smaller fans and aren’t available in passive configurations. And they’re usually more expensive than a more normal-sized build.
There are really two flavours of SFF PC: those with a full-power GPU (typically for gaming or professional use) and those that don't. For the latter, it shouldn't be too hard to build something even passively cooled. You can go even smaller. I know less about this space because it hasn't been my focus however.
Gaming SFF PCs are my jam and here the Louqe Ghost S1 holds up extremely well:
1. It takes almost all double-slot cards. Getting something a little shorter can help in terms of getting the card in and out and for cable management but there's really no need to shop for a specific shorter model. The more than two slot cards (eg RTX 3090, RX6900XT) won't fit but say a 3080 (assuming you can even get one) will be just fine;
2. My personal preference for PSU is something like the Corsair SF750. It's a 750W highly-rated SFX form factor PSU. It works well, can power a 3080 system and seems to be relatively quiet;
3. The Ghost with a top hat can then mount something like an NZXT Kraken X530 AIO to cool your PC. This is going to cut down a lot of your noise; and
4. With a separate top hat on the bottom of the case you mount two quality Noctua 120mm fans in exhaust (meaning it pulls air from the case).
The net effect of all this is that air is drawn in from the sides and expelled out from the top and bottom. It is also a negative pressure set up, meaning there is more force for exhaust than intake.
Positive pressure would be nice for keeping dust out of your case but negative pressure here is better for airflow and thus noise (by operating at lower RPM).
The above will have almost full case power and airflow and be relatively quiet. It won't be as good as you can get with a full or mid tower case but it's pretty darn close.
Not really any more. Most popular mini-ITX cases for enthusiasts support 240mm AIOs for CPU cooling. Noctua even has low-profile air coolers that fit in some mini-ITX cases and rival their biggest heatsinks in performance.
The SFX PSUs are slightly more expensive, but the good ones are so efficient that the fans won't even turn on during normal (non-gaming) use.
They do OK in noise-normalized tests, which are good for comparing and still relatively easy to perform. They're inadequate for quiet operation though. In fact the huge coolers I am using currently are barely adequate for their respective components - they require clearly audible fan speeds to avoid unhealthily high temperatures under sustained load. Certainly not extremely quiet; I'm not really happy with it, and I have the best air coolers with some of the best fans and the best thermal compound on the market and I have very carefully tuned fan profiles. Water cooling would offer slightly better cooling performance, but it has other issues - mainly pump and motor noise - plus it's rather expensive (more than 10x the cost of air cooling).
You can of course make an extremely quiet SFF build, just not with an upper-midrange CPU and a highend GPU. With the same components you can make a decently quiet mid-tower desktop, like I have.
("Extremely quiet", "virtually noiseless" and so on are pet-peeve phrases of mine - I'm always assuming that marketing people are half-deaf because they keep referring to stuff emitting 20 dBa or more like this.)
If your goal is as close to noiseless as possible, a big case with a lot of sound dampening material is the way to go.
However, the modern SFF experience is much better than you give it credit for. An AMD 5950X with a 240mm AIO in a mini-ITX case is easy these days and it keeps the CPU temperature in a reasonable range.
But if your goal is a no-compromise quietest build possible, obviously you don't want to get a small case.
> plus it's rather expensive (more than 10x the cost of air cooling).
I'm not sure where you're getting these numbers, but modern AIO water cooling isn't that expensive.
> I'm not sure where you're getting these numbers, but modern AIO water cooling isn't that expensive.
I could have been more clear here, I meant a custom-loop, not an AIO since they're a sidegrade to a top-end air-cooler at best.
> However, the modern SFF experience is much better than you give it credit for. An AMD 5950X with a 240mm AIO in a mini-ITX case is easy these days and it keeps the CPU temperature in a reasonable range.
I don't see the contradiction - you can have a quiet SSF build, and you can have pretty powerful SFF builds (enthusiast GPUs might be a problem), but you can't really have both at the same time... at least not under load.
The space is evolving. https://www.winterdesign.co/ -- this ultimately proved too expensive to produce in large quantities (due to the massive spike in the price of Aluminium), but it's a mini-ITX case with 2x280mm radiators.
I managed get one cheap-ish from the Kickstarter, and while it's got some flaws (and was a total bastard to build in -- it's a very small space to do a custom loop), it's everything promised on the tin; small, quiet, powerful (5600X and a 6800XT -- even when gaming the fans don't ramp above 40%, though admittedly that may change in summer).
> I could have been more clear here, I meant a custom-loop, not an AIO since they're a sidegrade to a top-end air-cooler at best.
Custom loop and an AIO of the same size are going to perform the same. I don't understand why you're suggesting that water cooling costs "10X" as much as air cooling when that's clearly not true.
An AIO and a custom loop with the same size radiator will perform the same. I've done custom loops and I've done AIOs. There's nothing special about a custom loop other than you get to mix and match different components.
Also, the top-end air coolers like Noctua perform almost as well as liquid cooling these days.
> I don't see the contradiction - you can have a quiet SSF build, and you can have pretty powerful SFF builds (enthusiast GPUs might be a problem), but you can't really have both at the same time... at least not under load.
I'm telling you - I have a 5950X and a 240mm AIO in a SFF and it's quiet. I could move the same CPU and the same AIO to a big case with sound dampening and it might be marginally quieter, but not by a huge amount. The only real difference is when I'm running the GPU at full tilt during gaming, but it's undervolted and I can't hear it over the game anyway so I really don't care.
