Noise reduction project

[HowAboutBob]

I have a full tower that sounds like a jet about to take off!

Lets count the fans:
120mm fan in front (intake)
80mm fan top back (exhaust)
Power Supply (PS) directly below it with 80mm exhaust fan
80mm fan below PS (intake- blows at CPU)
80mm hole below previous 80mm (not used)
a Winfast geForce 256 with standard fan.
Athalon 2100XP with a Thermaltake Volcano 7+
One WD 80GB drive with harddrive cooler http://www.newegg.com/app/Showimage.asp?image=35-888-106-01.JPG

I am replacing the 80mm over the PS with a 120mm Sunon after I dremel the hole out and install a screen.
I am removing the other 80mm below the PS and sealing up with rubber mat.

The rubber mat is part of a vibration/noise damping scheme I am working on.
I am applying to sides, ceiling and floor of the case.
I'd like to thank Renod from forums.silentpcreview.com for his suggestion

For sound deadener, I would target vibration dampening material as your case transfers vibration easily which is tranlated to sound. Best I have found for systems is from www.mcmaster.com and is Part number: 9709T19, Adhesive-Back Damping Sheet Polymeric Mastic,.070" Thk,.7 Lbs/SF, 32" X 54", Black, $ 12.79 Each . One sheet was big enough for 4 midtower systems and cuts easily with sissors or a box knife. Shipping was about $6 and it came right away. Also use their site search for other "dampening" products. They have everything. Best prices on the planet for every kind of commercial/industrial sound deadening material you can imagine.

I also bought 2lb 1 7/8" foam (like they used to pack in harddrives) in transit.
http://www.foamorder.com/products.cgi?cart=j1X0q0n34M23M35M951n7A6b5X&item=acoustic
The foam will be glued within case to absorb sound but not disturb air flow.

The Sunon fan is a screamer. 42 db but also 108 cfm.
I am keen to build an exaust like http://www.muffledcomputing.com/mufflers.html
I bought a plastic 3 drawer cart from K-Mart for $9.99
I will cut up two of the drawer to make a muffler and pad with the foam.

If this is insufficient, I will undervolt my fans using a 5 volt and 7 volt wiring adapter out of a Molex Y adapter
Thanks again to Renod for that one http://www.dslwebserver.com/main/fr_index.html?/main/5-7-adapter.html

Gotta watch the temps

BTW I have an ASUS A7N8X with their fan monitoring software.
Only mobo and CPU is being monitored, not power.
If this is Power Supply, How do I hook this up?

Any other advice out there?
Bob

 

[godmare]

Yes, on your Volcano 9: remove the ThermalTake steel grill completely... did this on my Volcano 9 and it's like 2 different fans
I also put o-rings between my fan and hs shroud, but I'm not sure you can do that with the 7...

Personally, I'd nix the hard drive cooler.. it's just extra noise, plus I'm not crazy about having dust crammed into my hard drive.

Get a passive cooler for your northbridge motherboard chipset and your gpu.

 

[godmare]

Whoops, I mean your Volcano 7+, not 9 or 7

 

[CaptnKirk]

RADICAL APPROACH

 

[HowAboutBob]

Originally posted by: godmare
Yes, on your Volcano 9: remove the ThermalTake steel grill completely... did this on my Volcano 9 and it's like 2 different fans
I also put o-rings between my fan and hs shroud, but I'm not sure you can do that with the 7...

Personally, I'd nix the hard drive cooler.. it's just extra noise, plus I'm not crazy about having dust crammed into my hard drive.

Get a passive cooler for your northbridge motherboard chipset and your gpu.

Taking off the steel grill.....hmmm, sounds interesting. I gotta try that!

Harddrive coolers not so loud, especially in comparison to everything else.
Of course, that may change as decibels drop (with any luck).

GPU fan is just a little thing. Its not too loud (I think) but I will keep in mind.
There already is a pretty honkin' big passive cooler on the northbridge.
Did you mean the southbridge, or did you think something else is required?
http://www.asus.com/pub/ASUS/mb/socka/nforce2/a7n8x/e1177_a7n8x.pdf

Bob

 

[godmare]

Okay, I assumed there wa a fan on your northbridge... rather, if there was a fan, then I would say get a passive heatsink
Personally, I'm weary of hard drive coolers.. pull yours of after it's been running for a few months and look at all the crap caked into your drive, then you'll see why.
When my V9 is turned all the way down, or even most of the way, I can hear my GF4 fan loud and clear over it. If I could replace it with something else, I would... read into your card, ask around onm Anandtech, I expect yours would be okay with the current heatsink and just unplugging the fan. Make suer you double check, though.

Also, look into a 3-way baybus or potentiometers/rheobuses for your case fans. See which you're more comfortable with and definitely do that for when your system isn't under load.
Remove any obstructions from in front of or behind any fans, ie grates, reducers, case parts Dremel anything open and out of the way that you need to, the lessened air turbulence and backpressure will reduce noise dramatically.

 

[HowAboutBob]

Thanks for the advice!

Stupid question here:
My Asus has software to monitor VCORE and three fans.
See pg 1-15
ftp://ftp.asus.com.tw/pub/ASUS/mb/socka/nforce2/a7n8x/e1177_a7n8x.pdf
How can I hook up another fan.... It is only monitoring two now.

Bob

 

[FenrisUlf]

Originally posted by: HowAboutBob
GPU fan is just a little thing. Its not too loud (I think) but I will keep in mind.
There already is a pretty honkin' big passive cooler on the northbridge.
Did you mean the southbridge, or did you think something else is required?
http://www.asus.com/pub/ASUS/mb/socka/nforce2/a7n8x/e1177_a7n8x.pdf

Bob

Sure it seems little, but to get any decent airflow those little fans have to spin at high RPM. Plus, I've had so many 40-50mm fans go bad on me that I replace them with something else before even installing them. You'll find that the sleeve bearing on them tends to fail (especially because the CPU fans are upside-down in the case) and causes a great deal of noise. Gradually your comp gets noisier and noisier until one day you think to yourself "WTF is that noise? I thought I built this thing quiet!" I've replaced plenty of those little fans where they were audibly the noisiest thing in the system (louder than a 120mm and four 80mm fans combined!). If nothing else, remove the sticker and give them a drop of light machine oil and replace the sticker. That should help extend their life.

 

[HowAboutBob]

Oil.
Thanks.... I swear I would never have thought of that!
Bob

 

[spanner]

My opinion is that you have way more cooling then you need unless you are an overclocker. I think you would be better off replacing all your fans with low CFM fans (<20dB) and getting a quiet power supply. The thing with sound dampener is it wont do much to stop the noise coming out of fan vents which is where the majority of the noise comes from. Also do you have an intake fan in front? or does your HD cooler act as one? . The 120mm fan idea is good but go with a quieter 1600 rpm fan. There is absolutely no way you will the able to dampen the sound from an exhaust fan (foam only works on high frequencies). Also put a passive heatsink on the geforce 256 (those tiny fans make the most noise).I guess what I am trying to say is go with standard methods of reducing noise before doing anything drastic, time consuming and expensive that is not likely to work.

 

[mechBgon]

From the experimentation I've done, my conclusion is that eliminating the source of the noise is the best first step. Anyway, I posted my starter recipe here: thread

 

[HowAboutBob]

Originally posted by: spanner
My opinion is that you have way more cooling then you need unless you are an overclocker. I think you would be better off replacing all your fans with low CFM fans (<20dB) and getting a quiet power supply. The thing with sound dampener is it wont do much to stop the noise coming out of fan vents which is where the majority of the noise comes from. Also do you have an intake fan in front? or does your HD cooler act as one? . The 120mm fan idea is good but go with a quieter 1600 rpm fan. There is absolutely no way you will the able to dampen the sound from an exhaust fan (foam only works on high frequencies). Also put a passive heatsink on the geforce 256 (those tiny fans make the most noise).I guess what I am trying to say is go with standard methods of reducing noise before doing anything drastic, time consuming and expensive that is not likely to work.

Spanner

If I undervolt the 120mm exhaust fan to 5 volts, I should get 45cfm at 23db.
I don't know offhand the model of my 120mm intake, so I can't tell you how many cfm or db, and at how many volts. I expect it to be similar.
the harddrive fans are pretty quiet but I may yank them anyway.

The PSU is from PC Power and Cooling: its the 300 turbo-cool atx and its fan is rated (by manuf.) as 35dfm ball at 42db.
I think that is the loudest thing going on here.
PCPC is a highly rated company but I was concerned that 300 is not enough.
Also read that two underclocked fans inside would be superior. I think Enermax does this but I don't know cfm to db.
Something quieter with a higher wattage would be great! I should just do it!

The volcano 7plus has a max of 49cfm at 47 db (high), unknown cfm at 35db (medium), and unknown cfm at 24db (low).
It is supposed to come with a resistor, but I did not get it! Is it possible that it is now internal?
If not, I have to complain!

I spent $10 on the kmart plastic drawers that I used for my muffler.
I spent $10 in the foam that I will put in case (conservatively, so as not to restrict air flow) and in muffler.
I spent $15 on the sound deadening material.
Not too expensive for an experiment.
If it doesn't work, I'll just yank it off!

godmare and you have convinced me that the gpu fan has got to go.

Thanks for the advice!
Bob

 

[mechBgon]

Originally posted by: HowAboutBob

Originally posted by: spanner
My opinion is that you have way more cooling then you need unless you are an overclocker. I think you would be better off replacing all your fans with low CFM fans (<20dB) and getting a quiet power supply. The thing with sound dampener is it wont do much to stop the noise coming out of fan vents which is where the majority of the noise comes from. Also do you have an intake fan in front? or does your HD cooler act as one? . The 120mm fan idea is good but go with a quieter 1600 rpm fan. There is absolutely no way you will the able to dampen the sound from an exhaust fan (foam only works on high frequencies). Also put a passive heatsink on the geforce 256 (those tiny fans make the most noise).I guess what I am trying to say is go with standard methods of reducing noise before doing anything drastic, time consuming and expensive that is not likely to work.

Spanner

If I undervolt the 120mm exhaust fan to 5 volts, I should get 45cfm at 23db.

With many DC fans, if you undervolt them to 5 volts, you get 0cfm at 0dB, and eventually a funny melting-plastic smell. Better think about this. *let me add that if you get them started at a higher voltage, you could probably bring them down to 5V, but starting from a stop is another matter*

Frankly, at work I use an Antec PerformancePlus880 (same chassis as the SX835II/SX840II, but with a TruePower PSU) with five of the very quiet 80mm NMB's. The case stays near room temperature inside, and the noise level is very low, with the loudest component being a 15000rpm SCSI drive (not as loud as you might think). If I fire up my old Quantum Atlas 10k SCSI drive then you can hear the system from one room away but that's just for an occasional system backup and then it goes nighty-bye again.

 

[greasepain37]

all but my cpu and power supply fans has been unpluged for about a week now. i just havent gottin around to plugin them back in. cpu is 34c and case is 42c and with no fans running my case is more dust free...its real quiet

 

[HowAboutBob]

Originally posted by: mechBgon
From the experimentation I've done, my conclusion is that eliminating the source of the noise is the best first step. Anyway, I posted my starter recipe here: thread

Thanks for the post mechbgon!
My reply ((italics)) next below your comments (bold, from your link):


If I were building a quiet PC with off-the-shelf parts I would probably go with

Antec 1080AMG case with TruePower 430W PSU
I have a steel case with a PC Power and Cooling Turbo-Cool 300 ATX which is tooo loud (IMO) and possibly underpowered (?)

dual 80mm NMB 18dB exhaust fans powered from the TruePower's thermally-regulated "Fan-only" connectors
120mm input and 120mm exhaust, which I plan on undervaulting to 45cfm at 23db

80mm NMB 18dB fan on Alpha 8045 heatsink
got that thermaltake volcano7 plus... gotta figure how to regulate it!

Ooops, forgot the CPU... something that doesn't generate a ton of heat, such as a Thoroughbred 1700+
too late, got a 2100XP

Asus A7N8X-Deluxe or EPoX 8RDA+ (passive northbridge cooling)
got that A7N8X-deluxe

Seagate Barracuda ATA V hard drive(s), far and away the quietest according to StorageReview.com
too much invested in harddrives... got WD 80gb (Jb series) and 60gb Diamondmax

Whatever optical drives you want, they only make noise until they spin down
Plextor UltraSCSI CD-ROM (pretty quiet) and Teac VeloCD (no idea yet because not tested yet).

Corsair XMS or other good RAM such as Mushkin, Crucial or maybe Kingston
one 512MB Crucail 2700

Some kind of passively-cooled video card
a small fan, undoubtedly "whiney", on a Winfast geForce 256, to be replaced I PROMISE

Cut out the rear grillework over the rear exhaust fans and either leave it bare or use chromed-wire grilles for low restriction/turbulence/noise
Got the wire grill for my 120mm fan..... just got to cut out the 80mm grillework and expand.

Stick some kind of soft material to the front of the HDD cage to damp vibration between it and the front wall of the case
Got tons of dampening material left... gotta try this!

You could also line the interior with Dynamat or thick, dense carpet if you really want to. The case has good intake vents that will allow the rear fans to pull air through the case without too much work. This setup would probably run a bit warm. You can flip the PSU over so it pulls the stagnant air from the top section of the case
Lined most of the inside with the dampening material.... damn its heavy! No need to flip the PSU because the 120mm exhaust is above the PSU

 

[HowAboutBob]

With many DC fans, if you undervolt them to 5 volts, you get 0cfm at 0dB, and eventually a funny melting-plastic smell. Better think about this. *let me add that if you get them started at a higher voltage, you could probably bring them down to 5V, but starting from a stop is another matter*

Frankly, at work I use an Antec PerformancePlus880 (same chassis as the SX835II/SX840II, but with a TruePower PSU) with five of the very quiet 80mm NMB's. The case stays near room temperature inside, and the noise level is very low, with the loudest component being a 15000rpm SCSI drive (not as loud as you might think). If I fire up my old Quantum Atlas 10k SCSI drive then you can hear the system from one room away but that's just for an occasional system backup and then it goes nighty-bye again.

Now you ARE scaring the bejeesus out of me! :Q
How can I start from 12 and bring it down to 5? or 7?

BTW, I forgot to mention that I have an old 10gb IBM SCSI-III drive in there which I am about to retire.
It is by far the loudest component and I can't wait to get rid of it!

 

[JKing76]

What can I use to cut the fan grillework and smooth the edges?

 

[mechBgon]

JKing76, you may be able to use a good pair of diagonal cutters (wire-cutting pliers) to nip out the grillework, then use a half-round file to smooth the edges. If you were doing this on the Antec case you would probably also want to drill corner holes and use fan screws to secure the grilles and fans, instead of the plastic holders the case comes with.

A Dremel rotary tool with fiberglass-reinforced cutting wheels is another versatile tool. USE SAFETY GLASSES! Two eyes per lifetime, maximum... make 'em last :Q

HowAboutBob, the system will only be as quiet as the loudest component, really, so you don't need fans any quieter than your loudest hard drive. The 23dB you're shooting for with your 120mm fan is still much higher than a pair of the 80mm NMB's at an estimated 19dB (and they would run even quieter on a TruePower's thermally-regulated Fan-Only connectors). *Most* fans will turn over and start reliably if they're on a 7V line. <-- (this is probably not true of fans that have their own thermal regulation or variable-speed dial, however)

The TruePower PSUs have a lot of power for their rating and a 330 would run your rig, but a 380 or 430 would leave you surplus power for your *next* computer a year or two down the road

Let me add that I almost always hear "Volcano 7+" immediately preceded or followed by "noisy," even on its Low setting

 

[HowAboutBob]

Thanks for all your helpful advice!
Bob