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> a bulky CPU heatsink and good quality fans spinning at no more than 800 RPM can give you a really silent desktop for a reasonable price

I’ve followed fanless PC cases for years, but I always arrive at the same conclusion: Modern fans, PSUs, and PC cases are so good that it’s not hard to build an effectively silent PC that uses fans for cooling.

My GPU and PSU don’t even spin up their fans at all unless I’m playing a video game, at which point I’m wearing headphones anyway. A large CPU heatsink allows for slow spinning fans that are so quiet I can’t tell if they’re spinning at all without looking at them. The case itself is lined with acoustic damping material to attenuate noise even further.

The loudest part of my recent builds hasn’t been the fans. It’s the noise made by the electromagnetic coils in the PSU. I had to swap power supplies to find an even quieter one, even though the fan wasn’t spinning.

I could see how a truly fanless PC could have used (recording studio or maybe a dusty environment where airflow isn’t an option) but for most of us it’s not hard to build an effectively silent case with good fan and component selection.

This is my experience too. Unless there's some sort of heavy workload going on you can have an "inaudible" computer fairly easily.

Something I've seen people fall for is the idea that water-cooled computers will be more quiet but that's definitely not the case. You'll struggle to find a water pump that is quieter than a decently air cooled PC (when not under heavy load.)

> Unless there's some sort of heavy workload going on you can have an "inaudible" computer fairly easily.

The catch with these fanless setups is that they're mostly limited to low-TDP CPUs anyway. You can't use the most powerful CPUs with a passive heatsink unless you add fans to help when the workload peaks, which starts to defeat the purpose.

> Something I've seen people fall for is the idea that water-cooled computers will be more quiet but that's definitely not the case.

Water-cooled can be quieter for certain edge cases like cooling the CPU and GPU. You have to work hard to keep the pump quiet, though. I've tried several of the popular pumps (D5, DDC) with various PWM strategies, but they're never entirely silent.

For CPU-only workloads, air cooling with a big heatsink is the way to go. A lot of people are surprised when they look at benchmark charts and see the best heatsinks outperforming most water coolers on the market.

> This is my experience too. Unless there's some sort of heavy workload going on you can have an "inaudible" computer fairly easily.

I agree and it doesn't even need to be a custom built computer. Any laptop with 15W TDP CPU with a power saver governor would be completely silent for most day-to-day task.

Since they are usually entry level the cost saved can be invested in buying nVME storage, RAM and what not. Many have USB 3.1 with display port and if connected to a monitor you have easy access to the more ports than a >$1000 laptop.

> Modern fans, PSUs, and PC cases are so good that it’s not hard to build an effectively silent PC that uses fans for cooling.

This is a lie. Or we have entirely different definitions for what silent means.

It’s pretty hard. I just did this with a pretty good budget. It’s taken a number of parts swaps to get to a truly silent PC.

Amongst the issues are:

- Lack of hardware/OS optimization. Coming from the Mac world, the coupling between hardware and software is much more loose. The driver quality is quite a bit more poor.

- Product variances. Eg. I had two fans of the same model that had different sound profiles.

> This is a lie. Or we have entirely different definitions for what silent means.

Maybe lead with the second sentence and drop the first? "This is a lie" is a pretty strong reaction to what you immediately acknowledge is likely just a difference in preference.

You're right (and it's too late to edit) but I'm just tired of the nonsensical "it just works" claims that keep on being parroted by people.

I researched silent PCs heavily before buying any parts and bought the best I could with that mission in mind only to find out that there's a bunch of gotchas and variations in QA -- even amongst the finest PC components. So I ended up spending even more money on more components and doing a bunch of A/B testing. I got to that silent PC goal, but with a lot of pain.

Another common one I see is "Switch to a Linux desktop. You can play all your favorite games!" The reality there being, yeah sure you can more or less play them as long as its not multi-player.

I am not a recording engineer (though my father was) but I suspect the more pragmatic approach to a quiet PC for your recording studio is to just put it in the next room and drill some holes through the wall for the cables.

True. Less radical thing I've done is placing the main unit next to heavy furniture in some distance from the actual desk, so it is mostly obscured for vision and sound waves it seems. With cabling and USB hubs (including those in the monitors) it remains pretty convenient. I'm sure you can go even further with standard sound dampening tricks if you care.

100% this. I have a system with a fanless PSU from Seasonic, 3 Noctua case fans and a Noctua CPU heatsink/CPU fan. I couldn't be happier with it. It is completely drowned out by any background noise (for example, the sound of typing, the hum of the AC, etc) and gives off a very, very faint whooshing sound when the house is truly silent. Personally I like the sound, it's the sound of high-end Austrian engineering working perfectly. I highly recommend Noctua fans.

This. I have a Ryzen 7 3700X-based machine [1] with the factory CPU cooler, an SSD, and a quiet system fan. When idle, it's inaudible even with the exhaust fan facing you. When I'm compiling, the fan speeds up but you can only hear a quiet ticking. Any quieter would have had no value for me.

[1] https://pcpartpicker.com/user/dtgriscom/saved/#view=P84p23

Each to their own. I have a 6 disk HDD RAID server in my sleeping room, because I find the random read and write sounds relaxing at night. It's not disturbing either, as the sounds are muzzled by a noise dampening case.

Using rubber grommets for all my mounts has made my HDD sounds so much quieter. An absolute world of difference.

What I would recommend if going for a quiet case with fans, look at 140mm low rpm fans. Disregard all midtower atx cases designed for use of 120mm fans.

You can safely use a fairly large passive cpu heatsink if with a 65W tdp cpu. Human annoyance noise from small DC fans increases as they get smaller (40/60mm size fans are perfect examples). A slow 140mm size fan can move quite a lot of air and very quietly.

There is no need to spend extra for 140. A quality 120 is negligibly higher CFM then a quality 140 at the same RPM.

It used to be that bigger is better, but there are diminishing returns, and manufacturers have started making quiet fans in all sizes

[Edit]

To be clear, if the case you like happens to have 140mm fan bays, that's fine, but no need to specifically look for that.

> There is no need to spend extra for 140. A quality 120 is negligibly higher CFM then a quality 140 at the same RPM.

Where do you get these numbers from?

Take Noctua fans for example, which are arguably some of the best on the market. A 140mm NF-A14 PWM [1] does have a throughput of 140.2 m³/h at 1,500 RPM, while a 120mm NF-A12x25 PWM [2]does only have a throughput of 84.5 m³/h at 1,700 RPM. And that even with the NF-A12x25 PWM being a newer generation fan than the NF-A14 PWM!

[1]: https://noctua.at/en/products/fan/nf-a14-pwm/specification

[2]: https://noctua.at/en/products/fan/nf-a12x25-pwm/specificatio...

Thanks for that, I'm apparently just wrong. I should point out that the 140mm doesn't get the extra airflow for free, as it's about 2dB louder. The lower frequency makes up for that though, and you will probably see more than a 2dB rise in noise for adding a second 120mm fan so it is still a net win at any given CFM.

Some review says that A12x25 + 14cm adapter is superior than A14 for silent setup. I can confirm that since I have both A12x25 and A14. A12x25 is impressive but a bit disappointed for A14's bass noise. dBA isn't a perfect metric how human feel the sound annoying

I agree, but I'm confident Noctua will tackle that with the next iteration of their 140mm fans which is currently scheduled to be released in Q1 2022 [1].

[1]: https://noctua.at/en/product-roadmap

A quality 120 is louder and has a higher pitched noise than a quality 140.

The pitch is largely related to the speed at which the fan is rotating. Louder is just not true, looking at the Noctua examples that your sibling comment posted, for the 140 and 120 in the same marketing range, the 140 is louder.

I would bet you that if you operated both fans in an perfectly empty, very quiet room with a human standing next to them, one at a time, the human-perceived level of noise annoyance from the 140 would be much less due to its lower pitch.

Additionally if you use a variable fan controller to reduce the rpm on the 140 to a point where its cfm or cubic meters/hour of airflow is exactly equal to the 120, or 5-10% greater than the 120 at its default rpm, not only will its pitch be lower, but its objectively measured loudness on a decibel meter will also be less.

It depends on what you need from the PC. There's a huge market of fanless mini PCs, which are taking generic laptop motherboards + CPUs (likely bulk orders of surplus from white-label ODMs) and putting them in thick aluminum enclosures. The CPU is mounted such that it directly contacts the case. For the <30W power output of these components, cooling is handled completely passively.

Depending on your workload, these can be great value for money (especially with CPUs that are a few generations old). If you need to do heavy compute, these won't fit your needs. For most desktop (as opposed to workstation) use cases, these are great.

https://www.aliexpress.com/wholesale?catId=0&initiative_id=S...

I used to build my own desktops when I was younger, but my most recent desktops have all been Intel NUCs, mostly due to valuing time/space/noise over raw price/performance (and due my rapidly declining gaming needs).

One feature that I've really grown to love that I don't remember ever seeing with custom machines is the ability to fully customize the fan-curve, including the ability to completely turn off the fan below certain temperatures.

This makes it as good as a truly silent build for most day to day use, but with effective cooling available for intensive tasks for when I need the extra power.

Maybe these days there are motherboards that allow you to configure the fan curve this way as well? I personally think this kind of configuration gives the best of both worlds.

Since you asked. Most of the motherboards I've worked with recently let you set a custom fan curve with the option to turn the fan off completely. You can also adjust which temperature sensor the fan curve is based on. This can be controlled for each fan connected to the motherboard.

Depends what you want to do with it.

I have a 0dB system:

https://www.amazon.com/Kingdel-Powerful-Desktop-Computer-Ind...

Works fine as my primary linux server.

I find myself more sensitive to unnecessary noise as I get older but "fanless" seems to be the Designers Dream while a fan is practical in terms of build cost and utility.

A fan CAN spin up and provide a LOT of cooling if needed. And stay still otherwise. An absence of fan provides no options.

I get a fan for my computer case. But lament service and retail centres with with echoing brick walls, polished concrete floors and hard surface ceilings. It isn't relaxing ambience, it is echoing noise...

I'm really happy with my integrated water cooling for my desktop, the large fan barely has to run and the water pump is almost inaudible except for the occasional gurgling noise. Its not the same sound as a whining small CPU cooling fan so much less annoying. The PSU fan also doesn't have to run much unless you really load the system. Been working well for almost 10 years.

> I just checked and just the DB4 seems to cost >200€ here in Europe

True, but you would likely spend about 100€-150€ for a decent case + CPU cooler (e.g. noctua) anyway. If you consider that, then the DB4 is actually not that expensive.

Fair point