Quiet PC...

Give up PC with tower cabinets and multiple fans.

Buy a Mac mini.

That's my vote too.

If there were a computer built like a Wii, (which is, of course, a computer of a particular type) I'd buy one in a heartbeat.

If your're into building stuff and DIY, you could possibly replace the noisy fans with TEC (peltier junctions)-- at least for the processor.

BG Micro and All Electronics both sell peltiers, surplus.

A lot of "overclockers" use liquid cooling. I don't know how much noise the pumps make. Google "overclocker" for info.

Or simply move the fan into the next room, or attic, and connect it to the PC via a clothes dryer hose.

From my understanding a TEC is a heat pump, so although it will move heat away from the processor it will also require cooling of its own. Since Peltier junction devices are not efficient cooling devices and require a lot of power, that power comes out in the form of heat. The net result is that the hot site of the TEC is much hotter than the processor on its own, which will require a larger heat sink and or fan. TEC's are great in that with sufficient heat sinks and fans they will effectively cool the processor colder than it would of been with just a heat sink. TEC's as far as my understanding won't do anything to allow you to run your pc quieter, at least nothing above getting a huge heat sink on the CPU directly which if large enough would allow you to eliminate the CPU fan. There are computer fans which are designed to be quiet, some of them you can hardly hear at all, I think replacing the fans in your pc with one of those would be the easiest route. The other source of noise in a pc is the hard drive, of which some brands are quieter than others.

...with TEC (peltier junctions...

Besides it's outrages price, Peltier needs to evacuate it's output heat from the opposite plate. How would you suggest this should be done, besides other fans, by a cascade of Peltier devices, all the way, out the PC box?

These are ideal for against-the-wall-mounting inside a sealed compartment of a flush assembly, such as a missile-cone for which (I was told) they were fashioned. A I terribly wrong?

Fans only become noisy, when they become messy and hence start to vibrate (this happens when the are heated and not left to rotate until cooled down before stopping). The main noise are HDD's, not fans, I think.

Try googling "fanless pc" or similar. There are quiet PC's out there that use just a special high conductivity heatsink with no fans, liquid cooling or peltier devices. I cannot remember the brands but someone here may remember.

Besides the Mac mini, you can go on Ebay and buy an older Mac Cube (also no fan) and have a museum peice as well as a quiet computer.

I've always wanted to toss my fans and replace each heat sink with a copper block, connected via heat pipes (small copper tubes or very thick guage copper wire) to one huge heat sink on the outside of the case, maybe attached to the back panel so it was vertically oriented and the rising heat would aid he cooling.

Heat pipes are not at all "small copper pipes or very thick copper cable". They incorporate a liquid medium and appropriate internal surfaces that enhance the vaporization of the liquid at the heat source, and the condensation at the cooler region, while wicking the liquid back to the hot end. Heat pipes maintain minimal temperature difference at their hot and cold ends, usually within just a few degrees, and can move large amounts of heat, which is much different than solid heat conductors, where the temperature drops off relatively quickly, and therefore the movement of heat is far less.

Many higher end motherboards now incorporate heat pipes in their cooling scheme.

http://en.wikipedia.org/wiki/Heat_pipe

Regards, Greg

Macs are more expensive, offer a lot fewer programs, have 3% market share by $$ (2% by units).

That said, since macs have a slightly easier learning curve they have garnered support in some non mechanical circles. Macs had the first good graphical user interface and desktop publishing programs, so they have a high support in that industry in terms of numbers. There was a day when you could only get pagemaker, and quark for the Mac. My first computer was a mac. I used to teach desktop publishing in high school with the mac. They clung to that dum 1 button mouse for far too long.

Eventually the schoolboard just bought PCs and tossed the macs due to costs once all those programs came out for the PC. The biggest problem was support. With PCs you could buy a taiwan power supply for $30. For an old Mac a replacement power supply was $300 or more...a straight ripoff.

That said. If you are not very mechanically inclined or computer literate a mac is a little simple out of the box, if costs matters not. Mac have far fewer virus problems as the share is so small few virus writers bother with it. It has no special immunity

I think you can use one of the many "fanless" PCs that are common in industrial locations where dust is a problem. There are actually many on the market.

Perform a search on any search engine for "fanless PC"

Here is one example:

http://www.stealthcomputer.com/littlepc_fanless.htm

If you don't plan to add a lot of boards to it...they are limited in space with most having one or two PCI slots...but if you want a small and quiet PC that is the way to go. Price is a little more than a standard PC... and the processors tend to be older, along the lines of Laptops...you may not be able to find one with the latest Core 2 Duo and such...

Oh, and since nobody said it yet, Welcome to CR4 !!

R.

Thank you, Rick...

A bit more info since my posting... I am currently using the following CPU... AMD XP 3200 (www.coolermaster.com) with a noise level of 24 dBA and a fan speed of 2200 rpm. To some it is a very acceptable level. I find it distracting and annoying in a quiet room which is the ideal setting for me. And since I am not a member of the wealthy elite I look forward to solving the "problem" at a minimal cost.

I have a Dell PC with a fan on the CPU and power supply.

It is about 1 year old and is very quiet. I hear the drive drive more than the fun.

I would try to find quieter fans and replace what you have...sometimes they get very noisy...I suspect that cheap version could be worse...try to find a good one...if all else fails buy a sound card and some speakers and listen to click and click www.cartalk.com or some other podcasts...there is lots of interesting stuff you can stream and listen too!

For low cost, I like Bhankiii's idea an post 3. Aluminum dryer duct is stiffer than vinyl and would probably propagate less sound. A nice system might be to build the fan (it would need to be bigger than the original to compensate for flow losses) into the wall in a neighboring room, using the space between studs as a duct. A short dryer duct from computer to wall -- and you'd be set.

Of course, some sound would be transmitted through the duct and computer box to the box's air inlets -- in fact, listening to my own machine here, I'd say half the noise is at the inlet.

Another possibility: put junction boxes in the wall in the computer room and the next room. Connect keyboard, monitor, etc through the wall to the next room where the CPU would reside. (You'd need to make up several short cables to do the pass through, and customize some outlet plates.) Less sophisticated would be to cut round holes in both wall surfaces, and just push the cables through, then stuff the space around the cables with a few old socks.

(Of course the person in the next room will do the same operation, in reverse, to retaliate...)

If you Google "quiet pc" you will come up with many links. This is but one: http://www.endpcnoise.com/cgi-bin/e/quietpc.html

There are many Web Sites devoted to this, especially if you plan on building the pc yourself. If not the link above is from a reputable PC maker that specializes in quiet PC's.

I agree with posts 1&5, or buy a (since you indicate limited budget) used (no more than a couple or 3 years old) laptop. I turn my desktop on mainly to do backups or format drives. I happen to prefer Macs, but I presume PC laptops are similarly quiet - once in a while I hear my fan, but barely...

There are tons of fanless case, power supply and heatsinks. Replace all the fans with lower rpm one will reduce noise. After that you'll hear the whine from the harddrives. There are watercool with external fanless heat sink tower.

You need two things to remove heat, airflow and surface area. With minimum airflow, you'll need lots of surface area.

The noise from the fans on pc's many times comes from the capacitor soldered across the fan input leads on the fan housing itself. A sympathetic vibration occurs. Try some silicone adhesive to silent the vibration. Put a glob over the capacitor. Might work.

That's a good idea, but the techniques is last ditch, you had better...

Some five years ago I was asked to audio record vocal poetry on a PC for someone at his private place.

As the ambiance noise was great we tried to record, when left alone in the apartment.

We found out most of the noise came from the PS cooler fan, and especially the Hard-Disk drives.

Then we thought of isolating the PC inside a large carton box with some rock-wool filled plastic-bags, and kept openings for necessary ports. It worked fine (from about minus 45 to about minus 70 db - as measured then and there) but not perfect.

Later, I found out he made a permanent wooden case which had even better figure, and took a better care of the issue of cooling.

Hi Pierre.

Welcome to CR4, I hope you enjoy it as much as I.

I built a PC from scratch some years back and built a special enclosure that used multiple fans running at a considerably reduced speed to reduce the noise. Another thing that I did was to use the fans to blow air into the enclosure rather than suck the air out and then filtered the air before it goes into the enclosure. By using multiple fans I could reduce the speed of the air that was required to cool the electronics and this reduces the noise considerably. In most PCs the fans suck the air out and this has the effect of making them nosier on the outside and turning your PC into vacuum cleaners that fill up with dust. By having the fans blow air into the enclosure and filtering it reduces the external noise and keeps the inside form being clogged up with dust.

Something you might like to try is building an enclosure that has sound proofing materials on the inside walls. I will need some kind of cooling and as others have suggested a ducted fan venting the hot air to either outside or some where the noise is not a problem, might be the way to go.

Keep in mind though the fans are there for a very good reason and no matter what you do you must employ some sort of system to transfer the heat from inside your computer otherwise it is going to be very costly repairing the damage.

I don't know what kind of space you have available, but I think the easiest and cheapest solution would be to get extentions for the monitor, mouse and keyboard cords and drilling a small hole through the wall and putting the computer in another room. This should eliminate the noise issue. Whatever other issues you have with space and/or the ability to drill though the wall are up to you. For noise sensitivity, distance can be a wonderful thing.