Building a silent computer
A somewhat obsolete article I still wanted to share
I started modding computers as a teenagers, when it was starting to be a thing. The year was around 2001 or so. For my next computer build in 2005 I actually spent considerable time thinking how I would make it as silent as possible within my budget. The next build four years later was even more carefully planned, and this time I didn't even care about budget that much. My current build from the beginning of 2013 was pretty much planned to the finest detail. It has served me well, and I kind of want to share my experiences in building silent computers, if only to give a history lesson how things were once.
The difficulty is not only finding silent parts, but to actually be able to squeeze out some processing power when necessary, for example when gaming or compiling.
Silent versus low-noise
Now there are different definitions of what is considered silent and what is considered low-noise. At the time I built my current computer I was living alone in a separate house in the middle of a Finnish forest. It was dead quiet there, especially in the night. The difference to a regular block of flats housing with central heating for example is quite radical, even if the latter would sound pleasantly silent in everyday living - like my current residence. But I know that for a true silent environment, I'd have to be away from any ambient noise, and that's what I use as my reference. I wanted to go for a truly silent PC, one that I wouldn't hear even in the quietness of the rural separate house. I was listening to a lot of music with high dynamic content, such as classical, and wanted to hear even the tiniest of details.
Most PC parts and consumer electronics in general that are advertised as "low-noise" are, to me, usually either unbearably loud or at least have a super annoying noise shape. Stuff sold as "silent" are usually things I wouldn't want to listen for more than a few minutes. That was the situation in 2013. Things probably have improved a bit from that, but it's something to keep in mind. For example, a fan might be considered silent if you have a refrigerator humming right next to you, but if there's no ambient noise, it might sound very noisy.
Eliminating sources of noise
You can put all the noise absorbing foam inside a case, but as long as you have air vents, noise is going to leak out. Therefore, it is much better to eliminate the sources completely rather than try to dampen them. Next I will break down my thoughts on how to eliminate noise from the most important parts of a computer.
The power supply unit is extremely important in the final picture, as it usually is not confined inside a case. For me, PSUs with a fan, no matter how low-noise, always made too much noise. The shape of noise might be comfortable, though - just a small hum of airflow. But I always go with passive PSUs. I used a 300 W SilverStone Nightjar ST30NF in my old build. I liked it a lot, but it made a tiny bit of buzzing noise and wasn't nearly powerful enough to begin with, so I had to find a replacement. For my current build I chose the Super Flower Golden Silent 500 W Fanless. I can highly recommend it: it is absolutely silent, not even any whining noise. It broke down after almost four years of use, but I got a replacement, as it has a five year warranty.
Nowadays, this one is pretty easy. Back in the days, around 2005, you'd have to carefully pick a motherboard which did not have a tiny fan. But motherboards with fans are long gone, and it's usually enough to buy one with good quality capacitors. Sometimes inductors might generate whining noise also, but usually a mid-range motherboard is good enough nowadays.
Do memory modules create noise, you say? Well, as far as I know, they don't. But they do warm up and need electricity. Therefore, always aim for the ones rated not only for speed, but also for lowest voltage rating. Less voltage means less power, which in turn leads to less heat to deal with, which translates to less cooling needed, ultimately leading to less noise. Also, if your new memory isn't working with the manufacturer specified speeds (which, I have found, is quite often the case), having low-voltage memory modules allows some leeway to try to fix the problem. For example, my memory modules are rated at 1.35 V (which, back in the days was super low for DDR3 memory), but I use them at 1.395 V just to achieve the rated 1600 MHz with low latencies.
Nowadays this is straightforward. Just go for SSDs. If you have HDDs, the Western Digital Green series used to be a good choice - especially the one platter version. HDDs consist of platters, and the more storage capacity they have, the more platters they have. Usually if there's more than one of a certain part involved, small differences in their operation (for example, spinning frequency) might create annoying noise image. This is especially true if you have two identical HDDs - sometimes their beat is very audible.
Mechanical noise from the HDDs is usually transmitted to the case as vibrations. For that I used to have a custom built HDD rack, where the HDDs were floating in air using strong rubber bands. It eliminates the problem completely. If the HDD has low reading noise and spinning noise levels, using rubber bands will probably render a slowly spinning HDD practically silent in most environments, so if you don't have the money to spend on SSDs, this trick still works well.
I haven't used the rubber bands in years, but I use my HDDs only when I need them. I usually use them as backup storage. My system runs on an SSD, and all my music is stored on SSDs also. Therefore I put the HDDs to sleep using
hddparm -Y by default.
This one is so much easier nowadays, as semi-passive units are readily available from stores. I had to build my own, using a FanAmp thermistor regulated fan controller, and a custom heat sink. My card is a Sapphire 7870 GHz edition, for which I bought an Arctic Accelero S1 PLUS heat sink, ripped all the extra plastic parts away, and installed a low-noise 120 mm fan, which starts spinning only after the heat sink starts to heat up. Just use as big a heat sink as possible, preferably with wide fin spacing. I've been extremely satisfied with the Accelero.
On my old build I had a Thermalright HR-03, but it wasn't good. It would require high pressure active cooling for anything more powerful than a lower mid-tier GPU. I even made an air flow guide from aluminium so that whatever air was passing from the bottom of the case upwards, it had to pass through the GPU heat sink, but the fin spacing was just too narrow.
This one is probably the most known and prominent, but probably actually not the most significant source of noise. There have been hundreds of CPU coolers on the market for decades already, and basically you have a solution for every need. Almost all of them nowadays have heat pipes, which really help to conduct heat. I have used the Thermalright HR-01 for my latest two builds now. It has a very wide fin spacing and is therefore an excellent choice for passive and semi-passive builds. I had to buy an extra part to align the heat sink in the angle I wanted to, and actually file away a piece from one of the heat sinks on the motherboard to fit the CPU heat sink mounting rack, so installation might not always be straightforward even if the selection available is huge.
Case and fans
I have tried at least a dozen brands, but I trust and highly recommend Noctua when it comes to fans. They create a good flow of air even when running at extremely low speeds. You will want to get fans with minimal power requirements, as it usually translates to high quality, and the less problems you will face with the initial spin-up phase when you turn on the computer. I have my back case fan controlled by the motherboard based on CPU temperature. In the front I have two fans running at extremely low speed (I used resistors to limit their spinning rate), constantly keeping a small but steady airflow through the case. When new, they were only audible from around 30 cm (one foot) away in the dead quiet environment, so they are practically silent.
As for the case, I've used a Lian-Li PC-A17 for my two latest builds. As I have a passive PSU, it's nice to have an aluminium case to conduct as much heat as possible. I do have noise absorbing foam installed to one side of the case, and I use pieces of foam to eliminate any freely vibrating large surfaces. In the picture is the FanAmp fan controller for my GPU heat sink fan and the resistors for the case fans.
The display sits right in front of your face and ears, so it's a shame if it makes noise. Back in the days when TFT displays were already the default, I was still using a CRT because a high-end CRT provided much better image quality for my use than even an expensive TFT. There were two reasons why I eventually switched to TFT displays: heat and noise. I was living in a small student flat and the heat generated by a big CRT was too much in the summer, and the display made an annoying buzzing noise.
That being said, also almost every TFT I've used has made a buzzing sound. It is really hard to find one which doesn't make any noise at all, and it's also extremely difficult to find reports on the noise as reviews tend to stick to image quality only. For the past three years I've been using a Sony KDL42W655A television as my display. Not only does it have superb image quality, it's completely silent. I considered buying a high-end Panasonic plasma television, but after realizing they make quite a bit of noise, I opted for the Sony.
Minigun, 2013 model
Here is my computer, Minigun, as it was four years ago. Not much has changed since. I first built the computer for Christmas 2012 to test things out, and made the tweaks for silent operation a couple of weeks later. The general idea is to slowly suck in air from the front, then force the air through widely spaced heat sink fins, and use a single temperature controlled fan to blow it out. The GPU heat sink fan is semi-passive. I have built some aluminium air flow guides to force the air where I want it to.
The motherboard is an ASRock Z77 Extreme4. CPU is Intel i5-3570, running at 4.00 GHz on four cores. The CPU heat sink turned out to be an overkill even with the overclock, if only I had the K version I could probably try at least 4.4 GHz when it comes to cooling power. The graphics card is a slightly factory overclocked Sapphire 7870 GHz edition, which is again easily cooled by the Accelero heat sink - it's more effective than stock cooling, which wasn't that bad to begin with. The PC also has six hard disks: two 500 GB Western Digital Green series HDDs, one 1 TB Samsung HDD, a couple of Intel SSDs and one OCZ SSD. There's also 16 GB of RAM, a DVD drive, an ESI Juli@ sound card, and a Matrix Orbital LCD display.
Back then it was not only absolutely silent in desktop use and low-noise in gaming use, it was also extremely fast. I'm not sure if such a build would have been possible ten years ago, but nowadays the market seems to have gone more and more to the semi-passive direction, which is what I was aiming for also. It doesn't hurt, though, to go through a checklist like the one I made above for each component when buying new hardware.