How quiet can a computer be?

I’m wondering how quiet a CPU can be, if I choose either not to overclock and to overclock a little. And are these fans capable of being quiet and able to provide sufficient performance for cooling?

I’m assuming you’re talking about a PC (since Apple sold the now-discontinued Mac cube which was completely silent). In theory, if you get a large enough heatsink you could cool it with a fairly inaudible, slow-turning fan. But you still have the power supply fan to contend with, which IME makes a lot of noise by itself.

If you choose specifically low power components and use large heat sinks, and pay a LOT of attention to getting rid of the heat passively, it is possible to make a computer that has no moving parts (no fans, no physical disk drive) and therefore would make no noise. They are used in industrial environments all the time, mostly due to the fact that fans suck in dust and things that move tend to get shaken apart.

There are fans designed to be low noise, which can be used to make a more practical personal type system.

*Originally posted by Running with Scissors *
(since Apple sold the now-discontinued Mac cube which was completely silent).

The Hard drive of my cube at work can be heard spinning, but you are correct, no fans. same is true of several of the iMacs.

The makers of the Vapochill PC claim that their system is not only the world’s fastest commercially available PC (3 gHz), but is quiet:

There’s actually a couple companies commercially marketing refrigerated PC’s.

Depending on the CPU and motherboard, your cooling options may be limited. If you have a board made by Asus or other lower-quality manufacturers that don’t follow AMD and Intel’s heatsink mounting specifications, there will be components in the way of a large heatsink. Alpha Novatech, a manufacturer of some hefty heatsinks, has published a Motherboard Compatibility Guide, which should give you general information even if you don’t decide to use an Alpha heatsink. Technically, if you simply used a power supply fan and a good heatsink+fan, the system may run properly. However, temps would be VERY high, and overclocking would be out of the question. I prefer aiming for low noise and good cooling.

Right now, the best heatsink on the market is the Thermalright AX-7 (AX478 is the P4 version). It uses 80mm fans, and I suggest the YSTech 80mm Rheofan (aka Manually Controlled). It has a dial that allows you to set the speed from silent up to moderately loud.

In a situation such as this where every little bit of temperature reduction helps, I suggest Arctic Silver 3 Thermal Paste, if you’re carefull about application. If you spill it accross the bridges on the CPU, you CAN fry stuff (Arctic Silver claims that it is non-conductive, but IMHO that’s just marketing BS).

I’d suggest an Enermax Manually-Controlled Power Supply. They have a dial on the back of the PSU that allows you to control the speed of the fans. I’d also suggest that you use Maxtor Fluid-Dynamic Bearing Hard Drives to reduce HDD noise. A PCI Slot exhaust fan, using sleeve bearings, to go in the first PCI slot would reduce system temps nicely and probably not produce any noticable noise. It might allow you to disable the fan on your videocard, which would probably make more noise than the exhaust fan.

Finally, you should use a single 120mm intake fan to keep the temperature of the entire system down. Sunon has a 69CFM quiet fan that I use, and it certainly lives up to its name. I tested by hooking it up with the case open and the fan in front of me, and I couldn’t hear it over the power supply, at all. I believe that Sunon also produce a 120x38mm fan that pushes 80CFM at the same noise level. This will reduce overall system temps nicely.

All of the above suggestions can be taken without modifying any components. If you don’t have any qualms about this, then replacing the chipset cooling fan with a large, fanless heatsink, doing the same for the videocard, and putting RAM sinks on your system RAM and videocard RAM might be beneficial, especially if you plan any overclocking, as you alluded to. Use Arctic Silver Epoxy to attach any heatsinks that do not have mounting mechanisms available. Most of the parts I recommended are available from and

As an aside, you may want to investigate watercooling if you’re experimentally minded, enjoy tinkering, and have a few hundred dollars and a few hundred hours extra to spare:)

Here’s a question: Would it be possible (and/or relatively easy) to develop a tiny microphone hooked up to an equally tiny speaker that, when pointed at a fan or hard drive, emits a sound wave of the exact opposing frequency, thusly cancelling out both sounds?

The Via C3 CPU requires no Fan for operation and you CAN buy solid state drives for something like $10,000.

Apart from that, you only have the PSU noise. I suppose you might rig up some sort of Laptop power brick arrangment to get rid of that.

A far simpler solution, however, is to just have your KB/Mouse/Monitor in a seperate room from your box.

I’ve read about people running their Pentium4 1.6Ghz Northwood CPUs without active cooling. Just the heat sink. The only way to do it is to undervolt it, though. Most of the aftermarket motherboards seem to be capable of this.

You’d have to expirement to find a balance between voltage and performance. As you lower the volts, you can lose stability at the stock speed and may have to underclock a little.

Seagate puts out a very silent hard drive, and I think Maxtor does as well. The Seagate is so quiet it’s freaky. I’m used to having some kind of audible notification that my HDD is being accessed.

Not really, because the fan isn’t a point source and the speaker wouldn’t be in exactly the same location, so there’s no way for the speaker to exactly cancel the noise out. Similar things are done in automobiles, and you do get a drop in noise levels, but it’s a fairly expensive solution.

And here my “simple solution” was to attend about three really good concerts…for several weeks EVERYTHING should seem quieter…

Seriously, I can’t hear my computer right now, only because (1) the central air fan is running and (2) the case is next to my coffee table, and the table and monitor are directly between me and the case. I do hear a computer fan…from the Raven’s computer, directly behind me, though.


Ah, phooey. I imagine that the setup can still be arranged - as long as the sound waves are emanating from roughly the same spot, counterwaves can probably be generated - although, the more I think about it, the more elaborate (and, thusly, expensive) the whole setup sounds.

Oh well. Just a thought.

You can assemble a silent PC from the CyberResearch catalog. Their smallest, 3-slot passive backplane chassis has no cooling fan (relying on free convection instead), and you put an all-in-one cpu card into it. They also sell flash memory “hard drives” with no moving parts. I guess if you require a floppy drive, there is no way to make it silent during its use - but these computers make no noise otherwise.

CPUs themselves don’t make any noise do they? I mean they are just a chip…

Hey, I saw a guy on the net who rigged up a water cooling system for his CPU. Yep,
cooled it with water, much like a radiator but no fan. Sounds like a fun project & not too noisy.

Right. The fan is necessary primarily because your typical Intel-compatable processor generates so much heat that using it without a fan is begging for a meltdown (the heat generated from other components inside the case is also a factor).

Using a CPU that generates less heat makes it easier for you to go fanless, like many of those afformentioned Apple iMacs.

Everybody’s talking about fans.

What about the annoying monitor whine?

Use a flat screen. LCDs don’t make any sound.


Although, now that I think about it, the step-up transformer for the LCD backlight may make a slight whine - although nothing as much as a CRT flyback tube makes. I’ll have to borrow my wife’s laptop and take it somewhere very quiet to see.

Never heard it, myself – I guess the hard drive and/or fan usually drowns it out for me.