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  • ff123
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"Silent audio computer"
Reply #100
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Do you have any ideas which of those had the most benefit?  My computer is currently much louder than I'd like it to be, but I can't really figure out why.  My CPU fan is essentially silent (it's variable-speed, and I set it by turning it to the lowest, then turning it up until it was barely audible above the rest of the computer noise, then turned it down from that).  My PSU is 40 dB according to silentpcreview.com (Q Technologies quiet PSU), and my case fans are all panaflow "quiet" fans.  But there's still quite a bit of noise.  It's not the hard drives, because I've manually spun them down (using hdparm in Linux) and they do make an audible difference, but not much of one -- maybe 1-2 dB.  So there's something else causing the noise.  I'm guessing it's either airflow in/out of the case or vibrations somewhere.

In my old system, my CPU fan was the loudest thing.  I originally had a Celeron 800 cooled by a Molex 60mm fan.  The next loudest thing was probably my IBM 60GXP 40 GB drive, once I took it out of the silencer hard drive sleeve (it was just too hot in that thing).  I already had a fairly quiet power supply (PC power & cooling silencer).  All in all, my old system was already pretty quiet, but I wanted something really quiet, while not going backwards in performance when upgrading.

So here are all the things I did.

1. Place the computer under my desk (away from my ears, with the desktop providing some blockage), near the carpet for sound damping, but raised off the floor to allow air to flow in from the bottom front.
2. Thermalright SLK800 CPU heatsink
3. Arctic Silver 3 thermal compound
4. Panaflo 80mm CPU fan (not a 60mm fan)
5. Undervolt CPU fan
6. Isolate CPU fan from heatsink with foam tape
7. Panaflo 80mm case fan
8. Undervolt case fan
9. Isolate case fan with isolating screws
10. Nexus NX-3000 power supply
11. Zalman heatpipe for my NVidia Ti4200 video card
12. Seagate single-platter 80 GB hard drive (7200.7 ATA/100)
13. NoVibes III hard drive suspension
14. Windows 2000 OS (vs. Windows 98 SE)
15. CPUIdle

I suspect your PSU is making the most noise in your system if you're having trouble isolating the problem.  I.e., it's easy enough to turn off all the other fans in your system to troubleshoot, except for the one in your PSU.

ff123
  • Last Edit: 01 May, 2003, 01:56:08 AM by ff123

  • JEN
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"Silent audio computer"
Reply #101
Quote
Wow, that machine is going to be quieter than a whisper! How does it sound so far?

For the first time ever since I got my first computer back in 1994, I have been able to go to sleep in the same room, because I cannot hear it from that distance (about 3 meters).  However, I can still hear it a little when at the desk 

The mods I have done so far are:

1. Decoupled/Suspended the HDD - Pic (Only 25p for 1 meter of that elastic)

2. Cut out an 80mm inlet at the front/floor of the case - Pic

3. Temporaraly raised the case with some wooden blocks to improve air intake, until I find something better to raise the case with  - Pic

4. As the HDD is decoupled, it needed better cooling, so I suspended it a little above in new inlet - Pic.  HDD temp = 33C as I am writing this info

5. Duct-taped all other sources of air-intake,  I am sure 95% of the air is taken from the new inlet alone! - Pic.  Good job no one can see the back of the case or the insides of the sides

6. 3x Zalman fans.  1 80mm for the PSU turned down to about 7v, 1 80mm for case exhaust turn down to 5v, and 1 92mm for heatsink turned down to 5v - Pic

Current temperature readings at 100% CPU load for half and hour (CPU-64, SYS-34, HDD-30 to 35)

7. Replaced the Heatsink + fan on GPU with Heatpipe heatsink - Pic.  You can just about see the GPU heatpipe directly below the 92mm zalman.  The fanmate is resting ontop of the heatpipe!

Mods before the end of May:

1. Replace 80Gb HDD with 80Gb Barracuda IV or V.  If I can't get hold of these it will be the 7200.7, which will be suspended in the same location as Mod #1 above

2. Replace all 3 Zalman fans (both 80mm and the single 92mm) with 3x 80mm Panaflos all attached to the back of the case exhausting air.  As there will be no fan blowing air directly at the Heatsink, 1 of the 80mm panaflos will be ducted to the Heatsink! (Exhausting hot air from the heatsink straight out of the case).  All 3 fans will be no more than 7v.  I am hoping only to use 2 80mm panaflos (for the PSU and Heatsink exhaust).  I will only use the 3rd Case exhaust if temps are too high!  (Maybe even a home made on/off switch for the 3rd fan just in case things get too hot )

3. Replace flower Heatsink with SLK800, as I have an xp1900+

4. All fans, including the 1 in the PSU (and maybe even the PSU itself) will be held in place with rubber isolation mounts, hopefully getting rid off all vibrations

Future mod - after May

1. Completely cover the inside of the case with "melamine foam" only leaving the inlet and exhausts for  good air flow.

2. Move the case from ontop of the desk to under the desk, Hopefully all this should make it completely inaudiable.

What do you think?

[edit]  typo...  [/edit]
  • Last Edit: 01 May, 2003, 08:10:27 AM by JEN

  • Annuka
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"Silent audio computer"
Reply #102
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What do you think?

I think I want a digital camera too.

Seriously, it looks good and quite expensive. But since you are going to cover the inside with melamine foam soon,it seems the computer is not dead silent yet. You probably have turbulence problems as well. Check if your quiet exhaust fans makes more noise when the case is closed. Covering the inside helps. Round IDE cables can help a little as well. You should also tie together your cables with cable strips - it also pleases the eye..

  • Annuka
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"Silent audio computer"
Reply #103
My current computer is dead silent from 30 cm from front and 60 cm from PSU fan. The modifications were quite simple and not extremely expensive:

- Covered all holes with duct tape.

- Using two slots below graphics adapter as inlet.

- Removed 3 cm fan from graphics adapter (Nvidia Quaddro Pro 4 - gets really hot).

-  Removed (lownoise) PSU fan and mounted it a on aluminium rail with cable strips. Mounted fan+rail directly in frot of graphics adapter - turned fan down to 6V (silent). The graphics adapter now has a 8 cm fan instead of a 3 cm. Rail is around €4.

- Placed hard drive (Seagate Baracuda IV) in Novipes - around €21.

- Turned CPU fan (P4 -northwood2 2,4 GHz in-a-box fan - 6 cm) down to 5V (silent).

- Placed large silent radial cooler outside cabinet on the PSU hole -  around €70, but I got it for free :)

- Covered inside of case with "Magic Fleece" - €60.

- Round IDE cables - €20.

- Tied all cables together with cable strips or taped then to case (below Magic Fleece).

- Zalman Multi Fan Controlle - sits in a 5,25" external drive bay and can control the speed of 4 fans - €40.

Total price just below €200.

Unfortunately there is a little but - it can only run for around 20 minutes at 100% CPU - then the mainboard temperature exceeds 50°C. Not a problem for me since I don't use my workstation for encoding and only rarely for games. When the temperature is too high, the monitoring software pops up and I simply turn the dial for the PSU fan up to 7V. I am pretty sure this could be fixed by replacing the standard 6 cm intel cooler - but that is a future improvement.
  • Last Edit: 01 May, 2003, 09:27:14 AM by Annuka

  • JEN
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"Silent audio computer"
Reply #104
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I think I want a digital camera too.

Seriously, it looks good and quite expensive. But since you are going to cover the inside with melamine foam soon,it seems the computer is not dead silent yet. You probably have turbulence problems as well. Check if your quiet exhaust fans makes more noise when the case is closed. Covering the inside helps. Round IDE cables can help a little as well. You should also tie together your cables with cable strips - it also pleases the eye..

Yes, you are absolutely correct!  I did tidy up the cables a little after taking the pics, which reduced the temp about 4C for the CPU.  I also was using a SilentDrive Enclosure, but because of high temperatures, I ended up getting rid of it.  So most of the noice is the HDD.

Also I burn-up the PSU because I had the Zalman 80mm fan at 5v in the PSU.  I ended up getting an old 300W PSU from the computer in the loft which no one uses, now that PSU is also making noise as I have not modded it yet.

I think the only turbulance in the case is from the PSU.

About the rounded cables.  After reading this article/thread, it seems that flat cables are better than round cables, and also neater, it just takes a bit of time to get the cables like that.

How much I have spent already:

GPU Heatpipe - £35
1x fanmate - £12.99
2x 80mm Zalman - £14.99 each (that was a mistake)
Decoupling the HDD - 25p
cutting the new inlet, and removing the original case fan grills including the PSU fan grill and PSU intake - free! used gardening tools
2x 80mm fan guards - 1.49 each
ATX case + PSU - £5 from computer fair (350W PSU which came with it is now blown-up)

total £81.20   

Cost of components to get in the near future

SLK800 heatsink - £50 (i think)
3x panaflo 80mm fans - less than £8 each
80Gb Barracuda - £70
Isolation mounts - £4 for a pack of 4 (will need at least 4 packs total of 16 individual mounts)
1 more 80mm fan guard - £1.49

total £161.48   
estimated grand total £242.69     

Will be selling my old 80Gb HDD to a friend for £50
estimated grand total £192.69   

It should have cost £162.71 if I didn't get them Zalman fans

So it should be less than £200 (I hope), which is a lot more than I was expecting!

  • JEN
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"Silent audio computer"
Reply #105
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... - Covered inside of case with "Magic Fleece" - €60. ...

Waw!  That Magic Fleece is pricey stuff, it must be really good.  I was planning on getting some cheap stuff i.e. 24" x 24" 1/2" thick sheet of melamine foam for $2.57USD!  Probably no where near as good as that Magic Fleece 

"Silent audio computer"
Reply #106
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What do you think?

Sounds fantastic... a terrific model for anyone attempting to silence their computer!

I'm at about the same step as you on my silencing.

1. Purchased two Thermalright SK-7's @ $25 each, AS3 thermal compound, Zalman FB-123 fan bracket for GPU, and four ZM-FC1 adjustable fan controllers: $100
2. Dropped the case fan voltages and Fanmate'd the PSU fan to slow it down.
3. Ducted the PSU to keep it from burning up (apparently that didn't work well enough!)
4. Used spare rubber bands to make a crappy HD-suspension.
5. Got a dozen reasonably-quiet NMB 18cfm fans, tested them all, gave away the noisiest ones to a friend.  $20
6. Glued an old copper heatsink (350g!) to my GF3 Ti200 GPU with thermal adhesive.

I'm now waiting for a replacement PSU (last one just fried), at which point I will build an enclosure for my Maxtor D740x-BB screamer. Although I heard I can RMA my hard drive ("it's making a lot of noise!" ), cross my fingers and hope for a newer/quieter model to arrive, transfer the data, and send back my old one. That's a lot cheaper than actually buying a new drive, isn't it?

"Silent audio computer"
Reply #107
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The Nexus NX-3000 is now definitely the loudest component in the system, making a hum which is noticeable if I stick my head under the table near the computer, but not when I'm in my normal sitting position.  I'm not sure if it's the fan in the power supply or if it's the magnetics.

I think I'm done!

Hah, you're never done! You could stop the PSU fan with a pencil and find out if the PSU fan needs to go out the window.

Does your computer pass the "2am" test? That is, can you hear it in the middle of the night?

  • Continuum
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"Silent audio computer"
Reply #108
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Does your computer pass the "2am" test? That is, can you hear it in the middle of the night?

What is the purpose of that? Less noise from outside or when you are too drowsy to notice anything?

  • Continuum
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"Silent audio computer"
Reply #109
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My current computer is dead silent from 30 cm from front and 60 cm from PSU fan.

Really? 
The loudest part of my Computer is the PSU fan which is running at 5V most of the time, but I can easily hear it from 3 m in a silent environment.

  • ff123
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"Silent audio computer"
Reply #110
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Quote
The Nexus NX-3000 is now definitely the loudest component in the system, making a hum which is noticeable if I stick my head under the table near the computer, but not when I'm in my normal sitting position.  I'm not sure if it's the fan in the power supply or if it's the magnetics.

I think I'm done!

Hah, you're never done! You could stop the PSU fan with a pencil and find out if the PSU fan needs to go out the window.

Does your computer pass the "2am" test? That is, can you hear it in the middle of the night?

I found out the slight hum was actually coming from my hard drive.  When I shifted the drive a little bit in the NoVibes III, it went away.

So now the loudest thing in my system is ...

LOL

No, I'm done, really.

ff123

  • Volcano
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"Silent audio computer"
Reply #111
(I didn't read through this whole thread, so please forgive me if this kind of question has been answered before.)

My PC is already extremely quiet really (it has only got a CPU fan plus an extremely quiet PSU fan), but my hard drive's noise (especially when it's being accessed heavily) sometimes annoys me if I have the PC work overnight and try to go to sleep less than 2 metres away from it. It's not the volume, it's the "sound", the "frequency" of it I can't stand. Now I'm wondering if these rubber suspensions would help in this case. I kinda doubt it, since the noise I'm hearing probably isn't the result of vibrations, but just the hard disk noise itself that escapes through the case.

So, would you think a rubber hard disk suspension would do the trick, or will I end up padding my case anyway (I've read that cork is an excellent and cheap material to absorbe noise and vibrations too, BTW)?

Any answer, or a link would be greatly appreciated.

  • ff123
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"Silent audio computer"
Reply #112
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(I didn't read through this whole thread, so please forgive me if this kind of question has been answered before.)

My PC is already extremely quiet really (it has only got a CPU fan plus an extremely quiet PSU fan), but my hard drive's noise (especially when it's being accessed heavily) sometimes annoys me if I have the PC work overnight and try to go to sleep less than 2 metres away from it. It's not the volume, it's the "sound", the "frequency" of it I can't stand. Now I'm wondering if these rubber suspensions would help in this case. I kinda doubt it, since the noise I'm hearing probably isn't the result of vibrations, but just the hard disk noise itself that escapes through the case.

So, would you think a rubber hard disk suspension would do the trick, or will I end up padding my case anyway (I've read that cork is an excellent and cheap material to absorbe noise and vibrations too, BTW)?

Any answer, or a link would be greatly appreciated.

The suspensions are better for attenuating seek noise than they are for attenuating spin noise, so you should find them to be of great benefit.

ff123

  • JEN
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"Silent audio computer"
Reply #113
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(I didn't read through this whole thread, so please forgive me if this kind of question has been answered before.)

My PC is already extremely quiet really (it has only got a CPU fan plus an extremely quiet PSU fan), but my hard drive's noise (especially when it's being accessed heavily) sometimes annoys me if I have the PC work overnight and try to go to sleep less than 2 metres away from it. It's not the volume, it's the "sound", the "frequency" of it I can't stand. Now I'm wondering if these rubber suspensions would help in this case. I kinda doubt it, since the noise I'm hearing probably isn't the result of vibrations, but just the hard disk noise itself that escapes through the case.

So, would you think a rubber hard disk suspension would do the trick, or will I end up padding my case anyway (I've read that cork is an excellent and cheap material to absorbe noise and vibrations too, BTW)?

Any answer, or a link would be greatly appreciated.

My HDD is extremely noisy!  So I got a SilentDrive Enclosure and suspended the whole thing with some elastic (I have a link to a pic showing this somewhere in this thread).  The noise reduction was quiet amazing.

However, as it is a 7200rpm HDD, the temperature was a bit high so I decided to get it out of there.  If you have a 5200rpm HDD, I highly recommend a SilentDrive Enclosure, or something similar.  If you don't have a 5200rpm HDD, you can suspend it which will reduce the sound a little, but to get rid of the sound completely, get a quiet HDD.

This is what I will be doing shortly

  • Delirium
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"Silent audio computer"
Reply #114
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The suspensions are better for attenuating seek noise than they are for attenuating spin noise, so you should find them to be of great benefit.

If it's seek noise that's causing a problem, an easier solution is simply to turn on Automatic Acoustic Management (AAM) in your drive, which nearly all drives these days come with.  In Linux this is done with "hdparm -M n /dev/hda" where /dev/hda is your drive and n is an integer 128-254 (128 is quietest/slowest, 254 is loudest/fastest).  You may have to find a utility of some sort to do the same for Windows.  On my drives (both 7200 and 5400 ones) a setting of 128 makes seek noise just barely audible above the spin noise (whereas with the default 254 it's clearly audible several feet away).

  • Annuka
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"Silent audio computer"
Reply #115
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Quote
My current computer is dead silent from 30 cm from front and 60 cm from PSU fan.

Really? 
The loudest part of my Computer is the PSU fan which is running at 5V most of the time, but I can easily hear it from 3 m in a silent environment.

It naturally depends on the background noise and the mood I am in. Under normal circumstances it is quiet.

  • Mac
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"Silent audio computer"
Reply #116
Hrmm...  I started reading this thread, and on the advice I read early on, I replaced my horrific ThermoSonic CPU fan and heatsink with a Zalman 6000Cu flower.

With the fan at around half speed (half between min/max on the fanmate1) I am getting roughly the same temperatures (35C system, 45C cpu after load).  However, my computer is still noisy as hell.  I can sleep with it on, but its noticably noisy from 3m away.

I disconnected the 80mm exhaust fan at the front-bottom of the case, leaving an 80mm Cooler Master fan extracting around the CPU, 4 slots removed below the gfx card, and a noisy PSU fan.

Having spent £35 on the Zalman, I don't really want to go forking out for more things..  Is it reasonably easy replacing a PSU fan, or do you have to buy a new PSU? I'm wary of messing about with it, I'm pretty clumsy 

(sorry, but the thread really is too long to read, even though it is interesting!)
< w o g o n e . c o m / l o l >

  • JEN
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"Silent audio computer"
Reply #117
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... Is it reasonably easy replacing a PSU fan, or do you have to buy a new PSU? I'm wary of messing about with it, I'm pretty clumsy  ...

Yes, I found it very easy!  However, I cheated a little.  I cut the PSU fan off and taped them up with some insulation tape, and removed the old fan.  I then got the new fan and put it into the PSU.  Instead of soldering the new fan onto the PSU, I got a fanmate and used it as a cable extension (as well as slowing the fan down) and connected it to the motherboard

It is also supposed to be very dangerous to mess around with the PSU, as it keeps hold of power even when disconnected, so there is still a risk of getting an electric shock.  Make show you dont touch anything in the PSU except the fan

ps, I have the full copper flower heatsink too, but have the 92mm zalman fan at only 3.3v.  the CPU idle temp is 49C and the 100% load temp after 1/2 hr is 64C 
  • Last Edit: 02 May, 2003, 07:03:11 PM by JEN

"Silent audio computer"
Reply #118
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Now I'm wondering if these rubber suspensions would help in this case. I kinda doubt it, since the noise I'm hearing probably isn't the result of vibrations, but just the hard disk noise itself that escapes through the case.

So, would you think a rubber hard disk suspension would do the trick, or will I end up padding my case anyway (I've read that cork is an excellent and cheap material to absorbe noise and vibrations too, BTW)?

Suspending the drive will really help a lot. Just try putting your hand on the top of the case when your hard-drive is seeking; you'll feel the vibrations. The entire case is resonating when the hard-drive seeks, which makes the seeks much louder.

I suspended my drive primarily to quiet its idle squealing, and it helped a lot for that too. But it's still easy to hear, either idling or seeking, from my spot at the desk.

Try tying some rubber bands together into a big loop (snip the little loops, then tie the bands end-to-end), and sling it through some holes in your case to make a crappy HD suspension. Then carefully balance your HD in it. This solution won't last forever, because the bands become brittle after a couple of months. But it's an easy way to test the suspension idea. And if you decide it fits your needs, do what JEN did and spend a few cents (or whatever your currency is) on some decent elastic band material.

"Silent audio computer"
Reply #119
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I disconnected the 80mm exhaust fan at the front-bottom of the case, leaving an 80mm Cooler Master fan extracting around the CPU, 4 slots removed below the gfx card, and a noisy PSU fan.

Having spent £35 on the Zalman, I don't really want to go forking out for more things..  Is it reasonably easy replacing a PSU fan, or do you have to buy a new PSU? I'm wary of messing about with it, I'm pretty clumsy  

(sorry, but the thread really is too long to read, even though it is interesting!)

I would try replacing the PCI slot covers. Annuka has reported success with this technique (pulling air in along the GFX card), but there's a good chance it is simply sucking in the hot exhaust air from the back of your PC. You definitely don't want to recirculate the hot air; unless your GFX card is overheating, you probably want all the air coming from the front of the case.

PSU modding is fairly easy, as long as you think carefully before making irreversible changes. You probably want to unplug your PSU from the wall and wait some time before opening it. How long to wait? I've never heard a definitive answer, but everyone seems to agree that allowing the PSU to sit overnight should discharge the capacitors (hopefully). Then you can do something like what JEN did to add a new fan.

Try attaching the new fan to the outside of the PSU, if that's possible. You might have to cut away some case metal to gain access to the fan screwholes on the back of the PSU. This will lower noise due to air turbulence and also make it easier to switch the replacement fan to an even quieter one at a later time, if you feel it's necessary.

  • Annuka
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"Silent audio computer"
Reply #120
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I would try replacing the PCI slot covers. Annuka has reported success with this technique (pulling air in along the GFX card), but there's a good chance it is simply sucking in the hot exhaust air from the back of your PC. You definitely don't want to recirculate the hot air; unless your GFX card is overheating, you probably want all the air coming from the front of the case.

A friend of mine experimented with the concept. To minimise recirculation of the hot air, the computer should stand  at least 30 cm free of the back wall. The higher the computer case the better (really the distance from the pci slots to the PSU).

I had an Asus Geeforce3 a year ago. It overheated like crazy - 62°C idle - 86°C when playing 3D games. The pci inlet  gave lowered the temperature to some 37/52° C.

It might also work better for me, since I have a large radial fan mounted outside the case. It blows the air to the side not backwards.

  • Continuum
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"Silent audio computer"
Reply #121
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Try attaching the new fan to the outside of the PSU, if that's possible. You might have to cut away some case metal to gain access to the fan screwholes on the back of the PSU. This will lower noise due to air turbulence and also make it easier to switch the replacement fan to an even quieter one at a later time, if you feel it's necessary.

Why will there be less air turbulence? Just because you move it further away from the things crammed into the PSU? Is the difference noticeable/striking?

Or is removing the cover (grill) of the fan more important?

"Silent audio computer"
Reply #122
>> - I'm still hesitating about what DVD-rom drive I'll put in there. <<

Sorry if this is already mentioned elsewhere, but we still use the current 'Mad-Dog' series of DVD-ROM 16x Drives because they are inexpensive AND they promote themselves as a 'Quiet Drive' even when reading a DVD or CD-ROM Disk at high-speed. This is accomplished by dampening their tray, motor and spindle mechanism more than most others do.

They call themselves the 'quiet drive' because they want the unit to make as little noise as possible when reading a disk, so people can concentrate more on the Music or Movie, as opposed to hearing a loud 'rumble' coming from their DVD-CD playback device when the spindle revvs up in speed. And yes, there IS a noticible sound difference with this drive over the other more-generic ones. So it gets our vote.

  • JEN
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"Silent audio computer"
Reply #123
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Quote
Try attaching the new fan to the outside of the PSU, if that's possible. You might have to cut away some case metal to gain access to the fan screwholes on the back of the PSU. This will lower noise due to air turbulence and also make it easier to switch the replacement fan to an even quieter one at a later time, if you feel it's necessary.

Why will there be less air turbulence? Just because you move it further away from the things crammed into the PSU? Is the difference noticeable/striking?

Or is removing the cover (grill) of the fan more important?

Removing the grill is the minimum you should do to reduce the turbulance from the PSU.  Installing the fan on the outside is supposed to reduce turbulance further, but I have never tried it!

  • JEN
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"Silent audio computer"
Reply #124
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Quote
I would try replacing the PCI slot covers. Annuka has reported success with this technique (pulling air in along the GFX card), but there's a good chance it is simply sucking in the hot exhaust air from the back of your PC. You definitely don't want to recirculate the hot air; unless your GFX card is overheating, you probably want all the air coming from the front of the case.

A friend of mine experimented with the concept. To minimise recirculation of the hot air, the computer should stand  at least 30 cm free of the back wall. The higher the computer case the better (really the distance from the pci slots to the PSU).

I had an Asus Geeforce3 a year ago. It overheated like crazy - 62°C idle - 86°C when playing 3D games. The pci inlet  gave lowered the temperature to some 37/52° C.

It might also work better for me, since I have a large radial fan mounted outside the case. It blows the air to the side not backwards.

I have a Zalman heatpipe on my GF4,  How do I check its temperature?