Reducing computer noise

[Wolvenmoon]

Alrighty, I saw another thread about a guy wanting to soundproof his computers. Soundproofing isn't my goal, but reducing noise is.

I work on computers constantly, am a CS student. I currently run 3 in a single room, and will be setting up a 4th. Right now the sound is overbearing, probably just 3 DB under human speech (which is to say, half as loud.) It's distracting and obnoxious.

While I know I can't soundproof them - and I run them for performance so I don't want the added insulation - I've heard that I can cut out a lot of the excess noise. How would I go about quieting them? New, quiet fans are about 20 bucks a pop, and with 4 fans per computer that is just not an option. I'm on a student budget.   

I also need what ever method I use to be compatible with my method of cleaning my computers, I use a 1/2 HP blower used by dog groomers to dry out spitz breeds (Siberian huskies, samoieds,e tc) to blast the dust out of the systems. (It's grounded and made to not produce static in the dogs it dries). So needless to say, it moves some air. 

[johnbergstromslc]

If you can quiet your computers for 20 bucks a pop, I'd find a way to do that.  It's always best, if possible, to reduce noise at the source instead of trying to contain it in some kind of enclosure.  Any effective computer soundproofing is going to restrict airflow and create a lot more heat in the towers, probably leading to much more expensive problems down the road.

[Wolvenmoon]

Whoops, my bad, I meant the fans are 20 bucks each. One computer will take a grand total of six 120MM fans, though two others will be 3 each two 120MM and 1 80MM, and a fourth will be another six, 1 120MM, 4 80MM, and 1 92MM. The price for a 120MM quiet fan of high quality is at least $20 each, and the other fans are appropriately priced for their size, each 80MM is about 15 dollars. There are cheaper fans out there that are quiet, but they're low airflow. My computers are all also cooled on positive pressure - which means there is more air being pushed in by the fans than there is being cooled out, so insulating them becomes a bit less of a problem.

120MM fans: http://www.xoxide.com/120mmfans.html

80MM fans: http://www.xoxide.com/80mmfans.html

I think a picture of what I'm dealing with is in order. http://www.wolvenmoon.com/sharedfiles/movedroom1.jpg At any one time, three computers are on. The ones being insulated the most run cool already, so I'm not as worried about overheating as I am the noise.   

[brn]

I see it's been a while since this has been posted, but I just came across it.

Stuffing too many fans in a PC is a novice mistake.  There are very few cases in which a PC needs that many fans.  Two fans with good airflow will provide better cooling than ten fans with bad airflow.  Use one fan in the lower front and one in the upper back.  Route all cables so they don't impede airflow.  Block large holes in the case (I see open drive bays the picture), as they won't allow the air to flow the way it should.  Use temperature sensing fans.  Make sure fans are properly secured so they don't vibrate.

The above should make a dramatic difference in the sound output of your computers.  They won't be silent, but they'll be a lot better and might not cost you a thing.

Other ideas that may or may not be applicable:
 - Turn machines off.  Odds are you're not using all those machines simultaneously.
 - Put some of them in a closet or other room.  Long cables or remote access software will give you access.
 - Virtualize.  Chances are you could replace some of the physical machine with virtual ones.
 - Big slow fans are better than small fast ones, but you seem to have gone that route already.
 - Set hard drives to spin down when not in use (saves heat and sound).
 - Most of those machines could probably get buy with fanless graphics cards.
 - Remove cards that you don't really need (and then block the card slot in the rear of the case, so air flows properly).
 - Overclocking is over rated. 

If you're worried about CPU temps, makes sure your heatsinks have copper cores and that you use a quality heat transfer compound (artic silver).

[Wolvenmoon]

http://www.wolvenmoon.com/sharedfiles/monitors.jpg

Antec 1200: 3x 120MM intakes on front, 1x120MM side intake, 1xinternal 120MM fan, 1x top 180MM fan. Then there's the GPU fan and the CPU fan, which is also a 120MM fan.

Oddly enough, this isn't the system that needs to be quieted down. It's the system with 1x80MM intake and 1x120MM output that is loud, I have two such systems.

-Odds are right that I'm not using them all simultaneously, however in this case you shouldn't trust the odds. 
-This is my computer room, I keep them out of my bedroom.
-I do virtualize, in fact I run three VMs on my router machine.
-Yep
-Spin up and spin down are more stressful on the hard drives than the heat and continuous running are. Starting and stopping without pause every 30-45 minutes would kill 'em.
-I am a gamer, and a novice, self taught CGI animator. Already the absolute basics eat up about 80 megs of GPU RAM.
-When rendering animations, the difference in 4 minutes a frame and 3 minutes 45 seconds a frame adds up. As I can't afford workstation and server parts, I have to work with enthusiast parts, which can get the job done.

I use arctic silver, and when I buy coolers for my CPUs I use this guide: http://www.frostytech.com/top5heatsinks.cfm Currently I have a sunbeamtech core contact freezer.

The main issue is that I can't afford to replace all the fans on all my cases with quiet ones, which end up being about 12 dollars a fan factoring in shipping.

[cordis]

Hello,
So I'm working on the same kind of thing, putting some acoustic foam on the walls of a computer case I'm making.  You can always try to get quieter fans, and I've certainly done that, but there are some parts, like high-end graphics cards, where it's very hard to replace the fan, so having some sound insulation in the case makes sense.

But in the computer parts market, I keep running across stuff like Acoustipack http://www.acoustiproducts.com/en/technical-information.asp, and it looks ok, but it looks like the foam mat stuff that's sold here can be a lot thicker.  The foam mat stuff sold here doesn't have the magical sounding multi-layer structure as far as I can tell, though.  But I wonder how much of that multiple layer stuff is just marketing hype.  Does anyone know, would a thicker single layer foam mat work better than a thinner multilayer type thing?  Or should I be considering something more complicated, like constructing my own layered structure with 1/8" of foam mat, 1/8" of mass loaded vinyl, and 1/8" of foam mat?