Unless you’re constantly playing with one of those fidget cubes, your gaming PC is probably the loudest piece of equipment in your home office that doesn’t actually have a speaker. You could completely rebuild your PC into a efficient, low-power, water-cooled statement of subtlety…or you could buy these in-line adapters for a quick and cheap alternative.
A brand called Noctua (one of the better brands in PC fans and cooling) sells them on Amazon for just $8 a three-pack. They come in both 4-pin and 3-pin varieties, though the 4-pin version will work with 3-pin fans, so just get those ones for futureproofing purposes.
Then, just install them between your standard case fan and the electrical connection on your motherboard or power supply rail, and a built-in resistor cuts the power to the fan by about half, resulting in lower revolutions per minute and measurably lower noise levels. It’s especially useful for fans that can’t be controlled by software.
Exactly how much slower and quieter your case fans get will depend on the exact model of fan, and how fast it’s intended to rotate in the first place. Noctua says the adapters are designed exclusively for the company’s own fans, but they’ll work with more or less anything. We tried the gadget on the How-To Geek test machine (which actually doesn’t have any brackets for fans, since it’s an open-air case—but we can still connect the fans to the motherboard). It resulted in a 30% drop in decibels from an NZXT 120mm 1200RPM case fan—not bad at all for a couple of dollars’ worth of cable. Our editor also uses them on all his Bitfenix case fans in his main desktop.
These adapters aren’t an ideal solution for a full build, because there’s no way to adjust the amount of electricity they’re limiting to the fan itself. Like we said earlier, you’re better off controlling the fans through your motherboard’s firmware or desktop software (or, barring that, a hardware fan controller). But applied consistently to all the fans in a system, they should result in a noticeable drop in noise, while still allowing enough flow in and out to keep your PC thermally stable. Applied to something like a two-fan Mini-ITX build or an HTPC under your television, and they should make a machine all but silent, save for the GPU.
If you’re looking for more easy ways to keep your PC quiet, be sure to clean the dust out from the filters and fans regularly. You might also consider anti-vibration silicone mounting pegs for your fans, instead of standard steel screws.