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BYU Project to Silence Computer Fans 369

phunster writes "The New York Times has an article about Scott D. Sommerfeldt and his students at BYU who have created a noise suppression system for computer fans (drop of human blood required to read article). The technology is not new, he uses out of phase sound to substantially cancel out the sound of the fan. What is interesting is his implementation of the technique. While other systems place a microphone and speakers in the center of a room, he places four miniature speakers and microphones around the noise source itself. His results are promising."
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BYU Project to Silence Computer Fans

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  • by ControlFreal ( 661231 ) * <niek@@@bergboer...net> on Thursday May 27, 2004 @01:41PM (#9268833) Journal

    BYU Project to Silence Computer Fans

    We as /. computer fans have been discriminated for so long, that you'd think that we, as computer enthousiasts, have had quite enough....

    • First we are bullied as small kids...
    • Then we are bullied as high-school kids...
    • Then we couldn't (or can't) get a girlfriend...
    • Then we are shunned at parties (provided we are invited at all)...
    • Then we are looked at funny for griping about DRM issues...

    An NOW, these people that have been bullying us all along have invented a system that makes us keep our mouths shut... Just great...

    Pills... must... take... pills...

  • by KoriaDesevis ( 781774 ) <koriadesevis.yahoo@com> on Thursday May 27, 2004 @01:42PM (#9268841) Journal

    We've seen this before here [slashdot.org].

    • Nope..

      This one was posted by CmdrTaco and the other was posted by timothy.

      Completely different.

    • Nope... This one was posted by CmdrTaco and the other posted by timothy.

      Completely different. :)

    • *to rip from a previous post: Yes, but that post was from timothy. This one is from CmdrTaco. Completely different.
    • by lcsjk ( 143581 ) on Thursday May 27, 2004 @02:38PM (#9269704)
      Let's not get the cart in front of the horse here, and for those non-USA people, that means "Let's get things in the proper order".

      Maybe we should look at the fan design first. When Brushless-DC fans were first introduced in the early 1980's I evaluated most of the major brands. Blade shape and contour were major contributors to noise, but by far the worst was mounting the fan up against the panel wall with holes or a grill. Running slow also reduces noise. One company's blade design removed the high pitch wind noise and just left a low pitch rumble that sounded quieter than it was. Centrifugal "squirrel-cage" fans were much quieter than axial fans. Sleeve bearings were a little quieter than ball bearings, but had a much shorter life and will "freeze-up" once the oil dissipates. (I actually had this happen to my old computer.)Ball bearings get louder over time, but you'll replace your computer before then.

      Power supplies can reduce airflow requirements considerably by better heatsinks and/or using the chassis for moving the heat away from the hot components. Once the real design issues are tackled, the bell-and-whistles approach could then be used to further reduce sound levels as necessary.

      Dell mounts one fan deep inside the computer and the PS fan is quiet but near a wall. Six weeks ago I bought a Systemax and a Dell computer. Systemax sounded normally obnoxiously loud. Dell was so quiet, I thought it was not working, so I opened it to see if I could tell what was wrong. I was fooled by the sudden start of noise and then quiet.

      • by Doc Ruby ( 173196 ) on Thursday May 27, 2004 @03:12PM (#9270251) Homepage Journal
        Why can't they replace the bearings with magnets? And shape the fan blades to avoid the wasteful noise entirely, at least in the audible band?
      • Well, to REALLY get the horse before the cart I'd hope that SOMEONE would focus on building computers WITHOUT FANS. Apple has done this, others have. Heat sinks and convection can go a long way, especially when the computers we are used to these days are vertically oriented to begin with. Put the hot stuff at the bottom of a case with a tube over them that allows the hot air to by sucked up to a vent at the top. A slow fan could kick in to assist if things started to overheat. There are fans that oper
  • by Lehk228 ( 705449 ) on Thursday May 27, 2004 @01:44PM (#9268863) Journal
    If the fans inside your CPU are silent you wouldn't notice if one failed, my machine is fairly quiet but i would notice if it booted without the CPU or PSU fan running.
    • by stratjakt ( 596332 ) on Thursday May 27, 2004 @01:46PM (#9268913) Journal
      Any recent system can monitor the CPU and case fans RPMs (and temperatures) and shutdown/freak/panic/whatever if the fan stops spinning. There are a plethora of third party warning devices to this end as well.

      If my CPU fan stops spinning my computer throws a tantrum you can hear from space.
    • That's just silly. Most computers have temperature monitors on the CPU. If it gets to hot there are PLENTY of programs that will warn you or turn your machine off. Acoustic monitoring may not even work! It could easily be whirling loudly and you wouldn't know that the CPU was 80 C.

      A temperature monitor is the way to go in all cases.
    • You, sir, are an idiot.
    • If the fans inside your CPU are silent
      Don't worry -- they won't be silent. Only quieter.

      And besides, as others have suggested, there are better ways to monitor fans. And if you have several computers in your office and just one of the fans fails, how likely is it that you'll be able to hear the difference anyways? Especially if you're not listening for it?

    • I have trouble sleeping without the humm of my 6 cheap-noisy ass fans.

      I corrupted my dormmate as well. He said he had to turn on a fan to fall asleep over the winter break. \o/

      oh PC! Humm me to sleep at night and bask me in your warm CRT light by day!
    • That's why I've clipped a baseball card to my CPU fan with a clothespin.
  • by Anonymous Coward
    (drop of human blood required to read article)

    Not when you use this [majcher.com]

  • by ites ( 600337 ) on Thursday May 27, 2004 @01:44PM (#9268870) Journal
    Apart from the discomfort of wearing headphones over long periods, the noise-reduction works well in office environments. Cuts out more than just noisy PCs: also airco, neighbours, and fire sirens.
    • My headphones get me in trouble - like when the boss calls, or the phone rings, or my officemate has to throw things at me to get my attention.

      Once we had a tornado warning and had to evacuate the top floors of the building - but I was blaring Jethro Tull into my Sony MDR-V600s.
    • Cuts out more than just noisy PCs: also airco, neighbours, and fire sirens.
      You must have some magical noise-reduction headphones. The ones I have, from the low tech (plugs of foam you stick in your ear) to high tech (working like the system described in the article) do definately drop the volume of the noise around you, but neither makes it so you can't have a conversation with somebody, and certainly neither drowns out the fire alarm. (Those things are INCREDIBLY loud.)
    • That works great! Particularly when those damn fire alarms and blinking strobe lights go off, I can concentrate on reading slash



  • nice (Score:4, Funny)

    by Zungert ( 782766 ) on Thursday May 27, 2004 @01:44PM (#9268879) Journal
    This would be well worth it on 90mm tornados. Its pretty shitty having 4 of them right beside your bed trying to sleep while your linux e-penis uptime grows every night ;)
  • by superpulpsicle ( 533373 ) on Thursday May 27, 2004 @01:45PM (#9268887)
    I don't think this industry has come remotely close to making a fan that works. It's sad when people need tubes running to the bathroom just to keep the GPU or CPU cool.

    If you create a fan that doesn't need water and guarantees performance of a water cooler, I think it'd be a hit. I have never the gotten blue screen of death from a noisy fan. Look on any forum, people are not complaining about noise. People are whining about overheating...

    • >people are not complaining about noise

      Really? Then why is there a whole sub-culture of people working on quieting their PCs? You can now buy quiet PSUs, Quiet CPU coolers, and oversize case fans with variable speeds.

      When I upgraded from celerons to athlon XPs, I was amazed at the noise generated by the cooling equipment. Then I swapped out a few parts, and I can hear my MP3s again. My PC used to sound like a cheap vacumn cleaner, now it's barely audible, quieter than most laptops. It really impro
    • If you create a fan that doesn't need water and guarantees performance of a water cooler, I think it'd be a hit.
      It would also be impossible. The only way this would happen would be to use immense volumes of supercooled air. Liquids are a much better conductor of thermal energy; even inefficient liquid cooling systems are more efficient then air-based ones.
    • It's sad when people need tubes running to the bathroom just to keep the GPU or CPU cool.

      Do we really want to know what's running through those tubes?
    • There are dozens of highly effective aircoolers available. The problem is that people only buy the cheapest, crappiest heatsinks available. Get a Thermalright (NOT ThermalTake) cooler and you won't have problems. You can even get performance that is vastly better than your average loud cooler when using a silent fan, if you use a good Thermalright heatsink.
    • I care. For instance, I personally would rather have a completely silent computer, than one that ran twice as fast. I hate how noisy most computers are any more.

      Maybe this isn't an issue for you, but that doesn't mean it isn't an issue. Have you ever been in a server room? Sometimes they are so loud you can't even hear yourself think. I live in a cramped appartment, and my computer is in my bedroom. Ideally I would like to leave it on 24/7 but it is too damn loud to sleep near, so I have to shut it
    • What are you talking about? There isn't a general purpose cpu or gpu in the world that requires watercooling for normal use. Sure, you can't use the heatsink off an old pentium 133 to cool your brand new pentium 4, but there are very capable heatsinks to cool the newest, most powerful processors. Notice how I haven't mentioned anything about fans. That because fans don't matter nearly as much as a good heatsink design. You just need something that moves air over the heatsink. Fans have been used for h
    • Look on any forum, people are not complaining about noise. People are whining about overheating...

      Obviously, you're only frequenting forums that cater to overclockers. Most of us in the real world have absolutely no trouble with our computers overheating. On the other hand, spending eight hours next to a noisy machine (and then, for most of us, going home and spending another ten...) to enough to convince us that quieter fans would be a great thing.
    • Maybe you browse too many overclocker/performance freak forums...

      Anyway, fans are only half the problem. You can run a thousand CFM through your coputer case and it could still overheat. Heat sinks are required to transfer the heat to the air effectively.

      You can't have a heat sink larger than the computer itself. Not if you expect to sell them to anyone but a performance freak or machine farm. There are also practical limitations to the design of heat sinks that limit their size and shape. Heat sinks are
    • What are you talking about? There isn't a general purpose cpu or gpu in the world that requires watercooling for normal use. Sure, you can't use the heatsink off an old pentium 133 to cool your brand new pentium 4, but there are very capable heatsinks to cool the newest, most powerful processors. Notice how I haven't mentioned anything about fans. That because fans don't matter nearly as much as a good heatsink design. You just need something that moves air over the heatsink. Fans have been used for h
    • You aren't looking at the right forums [silentpcreview.com].
    • You just aren't looking at the right forums [silentpcreview.com].
    • Don't be a dumbass. Fans work fine for desktop CPU's working at their normal specified operating speeds. Your complaint is like bitching about your car engine overheating after you've been driving 70mph for half an hour... in first gear.
  • by RobPiano ( 471698 ) * on Thursday May 27, 2004 @01:45PM (#9268893)
    Blood Donation [nytimes.com]

    I don't know as much about noise cancellation as I would like, but I understand most of the concepts. Although the method described in the article certainly is very cool, I wonder if they couldn't get better results by redesigning the fan. It seems that the fan generates too much random noise. Is it possible to make a fan that has a more predictable noise source? It could even be a fan that is way noisier before noise cancellation...

    Another thought on this is that you really shouldn't consider the fan alone. The G5 has a beautiful interior with a ton of fans. Its not terribly loud, however, because the airflow is well designed.
    • Despite what the submitter said, the link works without registering. I had mod points but I figured I'd just mention it rather than mod.
    • Sure...but all the good thinkers on the subject get hired by the Navy for submarines. ;)

      I expect a lot of the same principles apply.

      One potential source of noise is rough edges. So get the finest sandpaper you can find and smooth the blades on the fan. The problem is that since it's plastic, it won't help much. You might get better results from using a material that's polishable.
  • by Fizzlewhiff ( 256410 ) <jeffshannon&hotmail,com> on Thursday May 27, 2004 @01:46PM (#9268901) Homepage
    Now if they could just silence the kids that come to my house to tell me about Joseph Smith.
    • Re:Next project... (Score:3, Interesting)

      by grahams ( 5366 ) *
      Pfft... I'll take a Mormon coming to my door over a Jehovah's Witness any day. Every Mormon that has come to visit me has been very pleasant and polite, and they have no problem taking "No" for an answer....

      Just politely tell them you aren't interested and they will politely leave. Mormon missionaries are not pushy.

      I've practically had to call the cops to get rid of JW's.
  • by zepmaid ( 694112 ) on Thursday May 27, 2004 @01:46PM (#9268906)
    Personally its them damn harddisks that piss me off.
    If only someone could suppress the disk noise..
    • "If only someone could suppress the disk noise.."

      A ballpen hammer will do the trick. But I know what you mean, my systems tend to have at least a three drive RAID in em. My co worker keeps going on about how I should get a MINI-ITX based system because you can run them fanless. He just dosn't seem to get that I cant hear the fans over the hard disks.

    • Get FDB (fluid dynamic bearing) drives. I have several of them in my ReplayTV units, which sit outside my TV cabinet, and I can't hear anything unless I put my ear to the case. This is a big deal because when I'm watching a movie on DVD, the last thing I want to be aware of is the whine of a drive that chewing on a bearing, in my living room. I don't know if they'll end up like my bearing drives, and finally start emitting horrible noises when they age, but if they do, it'll be time to replace, hopefully
  • No-reg link (Score:5, Informative)

    by Anonymous Coward on Thursday May 27, 2004 @01:46PM (#9268908)
  • by schon ( 31600 ) on Thursday May 27, 2004 @01:46PM (#9268911)
    Yeah, this is much simpler than just making the fans quiet in the first place, right?

    Wonderful. "Look, instead of paying an extra 50 cents for a higher quality quiet fan, you can use cheap fans and spend $25.00 in additional parts to make the computer quiet!"

    • yeah, this method also strikes me as being power-consuming, and impractical for that reason... although, the idea itself is pretty cool.
    • Wonderful. "Look, instead of paying an extra 50 cents for a higher quality quiet fan, you can use cheap fans and spend $25.00 in additional parts to make the computer quiet!"
      If you're an engineer, of course you do. I thought that was a given. So what was your point?
    • cheap fan [directron.com]

      higher quality, "quiet" fan [directron.com]

      Hardly 50 cents. And, I doubt an IC, four mics and four small speakers would cost 25$ in parts.

      You can engineer a fan with perfectly balanced blades, great bearings, and eliminate much of the mechanical noise due to vibration or friction. But what of the noise generated by the moving air itself? You can hear this clearly when you have a case full of "silent" fans, and it's every bit as annoying.
    • Ummm, I bought nice fans, and they still make noise when turned up. What's your point? Running a 92mm fan at 6000RPM is gauranteed to make noise. No matter how much you pay for it. Fans just aren't that quiet.
    • Quietness should be a design goal/philosophy from the beginning, not an afterthought; much like security. I think it's dumb to start with power-hungry CPUs and noisy fans, and then bolt on a 'solution' for quietness.

      One of the many things I don't understand about current computer hardware is the segregation between quiet/small/laptop and big/noisy/desktop/server components. If you can design a low-noise and low-power component, why limit its use to laptops and other portable/embedded devices?

      I understan

    • by ShavenYak ( 252902 ) <`ten.retrahc' `ta' `3htimsb'> on Thursday May 27, 2004 @02:23PM (#9269387) Homepage
      Or better yet, just design a machine that doesn't need fans at all. Honestly, the vast majority of home and office computer users could easily get by with a Via Eden chip, which can be passively cooled. Saves electricity too - the noisy fan is not the only problem with a CPU that draws 80 watts or whatever they're up to now.
    • It may not be simpler, but it may be easier.

      Quiet fans are harder than you'd think to make. Even if the motor and bearings are absolutely silent, the air itself moving through the fan enclosure makes a noise.
    • Presumably this system will also cancel noise from hard drives, CD-ROM drives, video card fans, etc. Didn't RTFA, so I'm not sure.
    • Wonderful. "Look, instead of paying an extra 50 cents for a higher quality quiet fan, you can use cheap fans and spend $25.00 in additional parts to make the computer quiet!"

      Well, if you have a very hot-running computer that really needs a noisy, high-RPM fan, it might be worth it. Yes, bigger (not faster) fans and cooler components would help more, but if you've just gotta have a dual Xeon workstation, and anything powerful enough to keep the thing running is bound to be noisy, then maybe a $25/fan prem
  • by CharAznable ( 702598 ) on Thursday May 27, 2004 @01:49PM (#9268949)
    For a second, I thought that BYU was going to hire big, burly henchmen to "take care" of us Slashdotters...
  • Get a computer without a fan. I've had my Apple G4 Cube for a few years now, only now really showing its age and completely silent. Well, except for hard disk access. Of course you can't get them anymore, and Apple's new G5s have 4 or 5 fans in them... So don't think this is just some sort of fanboy rant, I honestly think that good design can get around the need for fans.
  • by millahtime ( 710421 ) on Thursday May 27, 2004 @01:52PM (#9268980) Homepage Journal
    Will the same technology also work on my girlfriend? She is like one of those movies that is just better on mute.
  • Blood? (Score:3, Funny)

    by paranoid.android ( 71379 ) on Thursday May 27, 2004 @01:55PM (#9269021)
    drop of human blood required to read article

    Does it have to be mine?

    "Hey Bob, come here, I've got something cool to show you. Oh, and bring a thumbtack..."
  • I remember an old episode of Beyond 2000 (http://www.techtv.com/beyond2000/ , but the old Australian version) where they showed an anti-noise system that would fit into a car's exhaust system. Microphones would pick up the noise from the exhaust manifold, a DSP would generate the appropriate "Anti-noise" then subwoofers would inject the Anti-noise sound into a specially designed muffler. The demonstration would drive a big V8 Holden muscle car around, clicking the noise reduction in and out. Without it soun
  • The fan noise from a serious computer has long been the single bigegst noise problem in the modern digital recording studio. It used to be the most popular solution was putting your tower in a closet somewhere with long extension cords for the keyboard, mouse, and whatever else. I've seen this used in several studios.

    I think I speak for audio engineers everywhere when I say HALLELUJAH! This is a seriously practical and useful invention, hopefully it will be affordable!
  • I just unplug all my computer's fans. Now my computer doesn't make any noise.

    At least my fiancee is happy about that.
  • I just put 2 small extra fans into my p4 1.8 gzh machine (I went and got a nvidia fx chip and was worried about heat). It sounds like a friggin hair dryer. Although I've managed to tuen it out. I notice it when i turn it one and apaprenlty everyone in my 3 floor house notices the noise of this one computer.
  • by dpbsmith ( 263124 ) on Thursday May 27, 2004 @02:05PM (#9269142) Homepage
    An interesting project, but it certainly seems like a Rube Goldberg (Heath Robinson for UK readers) way to go about it.

    The Mac G5 approaches this problem by using lots of big, slow-turning fans. It's probably expensive, but I doubt that it's as expensive as active noise cancellation. And Apple did a very good job. The Mac G5 is not silent, but in normal operation it is quieter than any machine I've used since the fanless 1984 Mac and the Apple ][.

  • I found it amusing to have an add for noise *generators* come up along with the noise reduction article.

    [yes, I know it's not quite the same thing]
  • the computational power needed is roughly equivalent to one computer.
  • by nizo ( 81281 ) on Thursday May 27, 2004 @02:10PM (#9269199) Homepage Journal
    Why don't case manufacturers do away with the power supply and integrate a UPS into the case? Rather than have AC -> UPS (which converts to DC to charge batteries) -> AC -> Power supply (which converts to DC) why not cut out all the wasteful conversions? I could even see having room in the battery portion so you could upgrade to additional "plug in" batteries. Any thoughts?
  • I suggested this [slashdot.org] awhile ago for another article on silent computing. It got shot down quite handily, mainly because I can't speel verry whell. Anyway the people that did respond with things other than spelling mistakes had good insight into this. It seems this guy has come up with workarounds for problems they noted. -peel
  • To Quiet a Whirring Computer, Fight Noise With Noise

    Published: May 27, 2004

    THE constant drone of a computer cooling fan can be annoying. But a professor at Brigham Young University has taken an unusual step to mute this noise: more noise, produced in just the right quantities from tiny loudspeakers that surround the fan.

    "We make anti-noise," said Scott D. Sommerfeldt, a physicist who created a noise suppression system with his students. It is the latest example of a technology called act
  • The grind and vibrations of your harddrive is also a significant factor in computer noise(though with a good drive it becomes secondary to fans). I've set my own computer at a slight angle(the back on a pillow) to reduce this noise, even though it increases my chances of HD failure.
  • Me, (Score:3, Funny)

    by meshko ( 413657 ) on Thursday May 27, 2004 @02:15PM (#9269264) Homepage
    I use my good ol' AK-47 to silence them damn computer-lovin' freaks.
  • Barring cost, why not use the same technique as those filterless air purifiers [sharperimage.com]. They produce directional air flow, which I have always assumed the velocity of the air was a function of the amount of electricity used in the system.
  • The makers of speakers and microphones were too busy high-fiving each other to comment.
  • As others have pointed out, quieting a single fan is only a small part of the battle. Unless that's the only moving part in your computer it seems like a bad idea to need a separate antinoise system for every noise source.

    Instead, I would elect to design the case not only for airflow but also for noise "flow". I'd spray panels with some kind of dense material - automotive undercoat might work fine, or barring that, spray-on bedliner. Or, I would use an adhesive panel such as dynamat. This has the signif

  • I'd be happier if I could cancel the noise coming from the other people on my bus. There are days where I get off the bus ready to kill something.

    Eliminates inane chatter! Loud cellphone talkers banished! Never hear the high-frequency noise of other people's headphones! Buy now, only $29.95!

    I would sprain my wrist trying to get my wallet out to pay for it fast enough.

  • I quieted the fan in my power supply by jamming a metal fork into it. As soon as the blades of the fan came into solid contact with the tines of the fork, the fan stopped spinning and my computer has been much quieter ever since.

    About the same time, I noticed that my computer began actng strngly though so maybe ths wsnt teh bsts srlstuion aftr ahl....?


  • The solution is DIY (Score:3, Interesting)

    by Cervantes ( 612861 ) on Thursday May 27, 2004 @02:42PM (#9269788) Journal
    The solution is not more noise. I've heard rumours of evil things happening to your brain when the noise coming in one ear is slightly offset (time wise) from the noise in the other ear.

    Between the 6-8 desktops and 2 laptops floating around my desk at any time, my noise quotient was pretty damn bad, even when I took most of them down to the bare minimums of fan noise. Yes, I could have replaced all my fans with nice quiet ones, or modded the cases for noise reduction, but then I'd have to do that with every case, every time I changed up.

    The solution? I scored a cheap-ass enclosed LAN rack, got some cheap-ass wood cut for me at the store, and build my own LAN cases. The only fan in my entire 6'4" rack is a .7 Sonne, 130 CFM fan that is vented from all the cases (5 of them @ 19x19.5x7)

    My systems have never been cooler, the noise is so freakishly quiet that I'm still getting used to it, I've got more flexibility than I ever did, and with everything KVM'd, I've got a cleaner desk. Total cost? Maybe $200 CDN [insert "so that's $.05 US?" joke here]. And, on the bright side, with so much extra space in my cases, my mod list is getting bigger and bigger with all the nifty things I can do.

    Sure, noise cancellation works in the short term, but 8 hours a day or more? I'd be worried that some slight imbalance somewhere might screw with my brain or break my ears.

    Plus, my kick-ass blacklighted rack with piles of blinkenlichten is MUCH cooler than some wussy lil speakers.
  • by buddydawgofdavis ( 578164 ) on Thursday May 27, 2004 @02:44PM (#9269823) Journal
    I work in a computer music and acoustics research lab and we're always after a quieter PC. We've considered a solutions like this, but we've decided it wouldn't really be necessary for long. Here's why.

    Among the many reasons for having a hard drive in every computer, two of the big ones were the Microsoft vision statement, and the fact that the network was much slower than disk. The latter is no longer the case.

    The fact that network is now faster than local disk is a MAJOR development.

    We've experimented with RedHat 9 with nfs root on older hardware with no disk and no fans, with 100Mb bootable NICs. We found to our surprise that they ran faster than with standard (non UDMA) ide. So, we're trying it now with newer hardware and gigabit, and some BIG heatsinks. So far, so good. We can optimize the central storage for speed, and the systems do, in fact, run noticeably faster in most cases, in addition to being nearly* silent.

    We hadn't counted on the added bonuses, but there are many. We can change an entire system disk by moving dirs, reexporting, and booting the machine up. Poof, new system. We can install and uninstall packages on machines while they're off! We no longer have two or three extra gigs on each machine, all our nfsroots are from a single physical filesystem (so far) so they all have the same amount of free space, much more efficient! And if a machine offends you, you can yank the plug out. No local fsck!

    *Note that the machine is never truly silent. Without any fans or disks, you can still hear a certain noise that sounds like it's happening when the disk used to seek. It's the toroids in the power supply! The network traffic causes HF noise in the power lines, which is filtered in the power supply and causes the chokes to vibrate slightly. The noise is very low, it would easily be drowned out by the quietest of fans, but in a totally silent room with no other PC sound, it's quite audible. There is also some low and infrequent clicking while the machine is warming up and cooling down, due to the thermal expansion of the heat sinks. This doesn't happen during use, when the temperature is more or less constant.

    I'm supposed to document all this and I've been lazy, so if you want the rundown on booting redhat 9 without a hard drive, write to me and I'll finish the page and send you the link.
  • As well as silencing your computer fans, you can also silence your hard drive [bbspot.com]. Guaranteed you won't hear the sound of a whining hard drive ever again, or in fact any noise from your hard drive at all. One step closer to an all-silent computer system.


  • already have IP rights to that idea?
  • Unite!!!
    They may try to silence us, but they will fail.
    We will not go quietly into that dark night, we will go kicking and screaming...

    <sound of muffled voice whispering, patiently explaining>

    oh, well, carry on then...
  • simpler alternative (Score:2, Informative)

    by hb253 ( 764272 )
    Why bother with all this technology when you can reduce noise to a tremendous degree by using a nice quiet Nexus power supply, Nexus CPU fan, and quiet fluid bearing drive hard disk?
  • I thought it was, "BYU project to silence Cougar fans." But then I realized that the football team isn't a new project, so I knew I was mistaken.
  • I have tried the noise reduction headphones, and I can hear the cancellation noise just as loud as the other noise. I am guessing this affects other people too. If noise cancellation is an issue, why not run another fan exactly out of phase, rather than try to generate a noise that is the "opposite"? I think you'd have better results if it was a real fan (despite that the power drain would be 2x).

All science is either physics or stamp collecting. -- Ernest Rutherford