HydrogenAudio

CD-R and Audio Hardware => Audio Hardware => Topic started by: extracampine on 2012-10-15 16:25:47

Title: Noise from "silent" PC
Post by: extracampine on 2012-10-15 16:25:47
Equipment:

Thecus N5200B NAS - ethernet cable - silent PC - firewire cable - Weiss DAC2 - Nordost Red Dawn XLR cables - Classe CAP2100 - Atlas speaker cable - B&W 804s (with Soundocity Outrigger)

PC:

Known as the "CAPS version 2" - a custom PC build designed by Chris Connaker of the Computer Audiophile website (www.computeraudiophile.com). Mine was built by Small Green Computer who have linked in with Chris Connaker (http://shop.smallgreencomputer.com/CAPS-20-CAPS.htm).

PC specs:

Origen ae M10 case; Jetway NF96FL-525-LF motherboard;  dual core 1.8 GHz Intel Atom D525 processor; 2x2GB modules of DDR2 667 from Transcend; 64GB Micro Center SSD drive; SOtM In-Line SATA Power Noise Filter; SYBA SD-VIA-FW1E1H PCI FireWire card (6-pin); Casetronic PW-12V5A-L5 60w power supply. More details about the CAPSv2 available here: http://www.computeraudiophile.com/content/...erver-caps-v20/ (http://www.computeraudiophile.com/content/405-computer-audiophile-pocket-server-caps-v20/). It is running Windows 7 Ultimate service pack 1 64-bit.

Problem:

The PC, supposedly silent, emits a noise. The noise can be divided into 2 components; a constant "crackling" noise - this is quiet though audible with the ear near to the case. It seems to fluctuate if the PC is being used (e.g. scrolling down through a website or starting a program). Moving the mouse causes slight fluctuations in it. The second noise is the main problem - a constant high-pitched emission; this noise starts when the firewire port is connected to an external device.

The noise only starts when Windows boots up to the main screen (it is not there on the BIOS screens). The noise is definitely coming from the PC unit itself and not anything external to it such as the speakers. Given the effect the firewire cable has on the noise, I ran some tests:

1. All equipment off & connected - no noise
2. Monitor on - no noise
3. CAPS on - no noise initially, then system beep, then some noise when the Windows logo appears, then the continuous noise when the Windows welcome screen and then desktop appear
4. Unplug monitor from CAPS - 1 second pause in noise, then resumes

5. Switch on DAC (connected to CAPS via 6pin-6pin firewire cable) - 1 second pause in noise, then resumes
6. Switch off DAC - noise continues, no pause
7. Unplug power from DAC - noise stops
8. Plug in power to DAC - 4 second pause, then noise resumes

9. Unplug firewire cable from CAPS - noise stops
10. Plug in firewire cable to CAPS - 2 second pause, then noise resumes
11. Unplug firewire cable from DAC - noise stops
12. Plug in firewire cable to DAC - 2 second pause, then noise resumes

13. Unplug/plug in ethernet cable to CAPS - no change
14. CAPS off - noise stops

I have opened up the unit to take a look inside. It's not really possible to isolate where the noise is coming from; the red circle in the photo below given my best guess but it could be wrong:

http://i49.tinypic.com/1fwew2.jpg (http://i49.tinypic.com/1fwew2.jpg)

I tried disconnecting the SSD and booting up; I get a message saying "reboot and select proper boot device". There is no noise, though the noise only starts when the PC fires up into Windows anyway.

I looked into the firewire drivers on the PC. I tried a few different drivers that came with Windows, though they did not alter the sound. I then tried a driver from a third party (Unibrain - ubCore Firewire (Firewire 800 - IEEE 1394b) driver suite) and this significantly reduced the noise. However, when this driver was selected, the driver for my Weiss DAC2 seems to stop working:

http://i48.tinypic.com/2ltoy9h.jpg (http://i48.tinypic.com/2ltoy9h.jpg)

The DAC2 is not recognised as long as the Unibrain firewire driver is being used. If I select the Windows legacy firewire driver and then disable the DAC2 driver, most of the sound goes away also (though not all of it). Of course I then cannot play music through the system as the DAC is disabled. I have tried a different firewire cable (4pin to 6pin) and used a 4pin to 6pin converter; this should cut the power leg of the cable. However, again no difference in sound.

When I run the Weiss DAC2 controller info program, it detects the OH 1394 Host Controller as: (1106) VIA Technologies, with chipset (3044) VT6307/6308. Finally, I tried connecting 2 firewire cables concurrently (there are 2 ports on both the DAC and the PC). This reduced the noise, though music will not play on the PC.

As you can see I have struggled with this for a while - any suggestions greatly appreciated! 
Title: Noise from "silent" PC
Post by: itisljar on 2012-10-15 16:49:46
Remove firewire card and boot the computer, tell if the noise is still here.
Title: Noise from "silent" PC
Post by: phofman on 2012-10-15 16:52:37
Noisy motherboard is a rather common issue. Under load the on-board inductors deployed in the numerous step-down power supplies start emitting noise. Sometimes the cuprit are capacitors. Just google how people fight this noise https://www.google.cz/search?q=motherboard+...NNsvLsgbyp4DQDQ (https://www.google.cz/search?q=motherboard+noise+inductor&ie=utf-8&oe=utf-8&client=ubuntu&channel=fs&redir_esc=&ei=_zB8UMuNNsvLsgbyp4DQDQ)
Title: Noise from "silent" PC
Post by: washu on 2012-10-15 17:04:27
Your motherboard is a special one which has additional power conversion circuitry to generate the lower voltages normally supplied by a standard ATX power supply.  As the load changes on the firewire card the converters have to generate the power for the load.  Needless to say, the converters on that motherboard are designed with cost as their primary concern.  Not that I buy into the audiophile BS, but this is a rather poor and uninformed choice of motherboard for the use case.

Other than maybe using a USB DAC and putting less load on the converters, there isn't much you can do short of replacing the MB.
Title: Noise from "silent" PC
Post by: Arnold B. Krueger on 2012-10-15 17:14:30
Your motherboard is a special one which has additional power conversion circuitry to generate the lower voltages normally supplied by a standard ATX power supply.


I haven't seen a motherboard that lacked DC-DC converters for years and years. The root cause is CPU chips and other chips that require nonstandard voltages.  DC-DC converters almost always require some sort of energy storage device whether a coil or a capacitor or both. These parts especially the coils can easily become sound generators, whether by vibration of their coils or magnetostrictive effects on their cores. Capacitors can have dielectrics patricularly ceramics that function as acoustical generators just as easily.

Quote
As the load changes on the firewire card the converters have to generate the power for the load.  Needless to say, the converters on that motherboard are designed with cost as their primary concern.


The desire to minimize the power dissipation of CPU and other chips has a consequence being that their power use becomes more and more dependent on what functions they are performing at the instant. This gets reflected back to the power supplies and there you are!

It may be possible to encapsulate noisy parts in sound damping compounds.

Just guessing, but this sort of thing properly applied might help:

http://www.parts-express.com/pe/showdetl.c...tnumber=268-266 (http://www.parts-express.com/pe/showdetl.cfm?partnumber=268-266)

Thing is that anything that dampens sound will also inhibit heat dissipation.
Title: Noise from "silent" PC
Post by: skamp on 2012-10-15 18:03:37
$1,500 for an Intel Atom PC that's supposed to be completely silent but instead emits annoying noises? Sorry, but you were scammed!
Title: Noise from "silent" PC
Post by: washu on 2012-10-15 18:39:12
I haven't seen a motherboard that lacked DC-DC converters for years and years.

This isn't the standard DC-DC converters that every motherboard has, though it does have those as well.  It's also the +5V, +3.3V, and -12V converters that are normally found in the power supply.  The external brick only generates +12V.  Thus the voltages needed by the firewire card (and everything else in the computer) are being generated by components on the motherboard instead of in the power supply like a normal computer.  Those converters have to fit a price point combined with the rest of the motherboard and are almost certainly of lower quality then those found in a dedicated power supply.
Title: Noise from "silent" PC
Post by: phofman on 2012-10-15 20:13:32
This isn't the standard DC-DC converters that every motherboard has, though it does have those as well.  It's also the +5V, +3.3V, and -12V converters that are normally found in the power supply.  The external brick only generates +12V.  Thus the voltages needed by the firewire card (and everything else in the computer) are being generated by components on the motherboard instead of in the power supply like a normal computer.  Those converters have to fit a price point combined with the rest of the motherboard and are almost certainly of lower quality then those found in a dedicated power supply.


I have a regular ATX MB which is very noisy too. Any DC/DC converter is a potential source of noise. IMO it is good (or bad) luck and the only way is to test and replace with another piece.
Title: Noise from "silent" PC
Post by: Trondis on 2012-10-15 22:13:38
$1,500 for an Intel Atom PC that's supposed to be completely silent but instead emits annoying noises? Sorry, but you were scammed!


I spent a lot of money last year to make my PC silent. It didn't work. So I have bought a Raspberry Pi ($35) instead for music playback. My harddisk is inside a closet, connected to a cheap NAS adapter (Patriot Gear Box - costed $45). This system is cheap and totally silent. It is also very convenient - I use XBMC that is remotely controlled from my phone.
Title: Noise from "silent" PC
Post by: garym on 2012-10-16 00:44:35
or pickup a Squeezebox Touch (< $300). Will play almost any sort of audio file, including FLAC at up to 24/96 natively (or 24/192 with free EDO app).  Music resides on computer anywhere you want (back closet, basement) as long as connected to local network and running Logitech Media Server software. Touch can connect to local network with WIFI or ethernet.  Touch has analog outs, optical outs, and S/PDIF coax outs (all live at same time).  Can use USB out to *certain* DACs if using Triode's EDO app.  And importantly, TOUCH itself has no moving parts and is silent.
Title: Noise from "silent" PC
Post by: Brand on 2012-10-16 09:58:41
At least with regular desktop motherboards you can sometimes eliminate noise like this by disabling some power states (C1, C3..) in BIOS.

I'm not familiar with Atom motherboards, but see if there's something like that to try.
Title: Noise from "silent" PC
Post by: googlebot on 2012-10-16 10:24:53
In 2001 I spent considerable efforts to manually eliminate my PC's noise in my student apartment. It was quite effective, but from the day I had implemented the changes, I started hearing my fridge, that I hadn't noticed until then.

Out of curiosity I turned off my fridge and noticed how the world outside the window immediately got louder. In the end, I lived happily with the moderate sound of my PC, the fridge, and the outside world and stopped worrying.

I agree with skamp, $1500 for a non-quiet Atom package: you have been scammed.

Title: Noise from "silent" PC
Post by: Porcus on 2012-10-16 13:19:54
Is that thing getting hot? If not ... a padded box?
Title: Noise from "silent" PC
Post by: Cegadede on 2012-10-16 14:44:21
I solved the noise problem by using an old eeepc 701 as my music player. I installed ubuntu server on it and mpd as the music player. The music is stored elsewhere on my home network and is mounted on the eeepc via nfs. As I didn't install a graphical user interface on the computer, I keep it's lid closed. Also, I've checked that music playing only uses less than 3% of the cpu, so it stays quite cool, allowing me to take of the cpu fan, wich made the pc completely silent.

I have it connected to a benchmark dac1 USB DAC and from there to a pair of denon POA-2800 power amps connected to a pair of Martin Logan's CLX ART speakers. 

The great thing about the eeepc 701 is that you can get one for less than US$50.00 and, for use in audio, it can be made totally silent by just removing the cooling fan (If you can hear it spining, I couldn't, but took it off anyway).
Title: Noise from "silent" PC
Post by: Arnold B. Krueger on 2012-10-16 15:40:28
I haven't seen a motherboard that lacked DC-DC converters for years and years.

This isn't the standard DC-DC converters that every motherboard has, though it does have those as well.  It's also the +5V, +3.3V, and -12V converters that are normally found in the power supply.  The external brick only generates +12V.  Thus the voltages needed by the firewire card (and everything else in the computer) are being generated by components on the motherboard instead of in the power supply like a normal computer.  Those converters have to fit a price point combined with the rest of the motherboard and are almost certainly of lower quality then those found in a dedicated power supply.


The quality of DC-DC converters in dedicated power supplies is often about as bad as they can get and live until next weekend.  ;-)

Seriously.

Their biggest advantage from a noise standpoint is often the fact that they are inside a fairly heavy tin box with a fan blocking the biggest hole.

Also, there is often just one SMPS in the PS box, with multiple secondaries on the transformer and individual filters for each voltage. That SMPS has a fairly large steady load on its 12 volt output. So, you don't have a SMPS with a highly variable load.
Title: Noise from "silent" PC
Post by: extracampine on 2012-10-16 16:27:03
Thanks for the replies all. I like the story about the fridge! 

Washu - are there any motherboards you could suggest? My DAC (Weiss DAC2) doesn't do USB - it has firewire, XLR, RCA and toslink.

I couldn't find anything about C1 etc powerstates in the BIOS.

Would getting a better power supply help? Or a power regenerator such as from PS Audio (http://www.psaudio.com/products/power/pw-power-plants/p10-power-plant/).

Thanks

Title: Noise from "silent" PC
Post by: mzil on 2012-10-16 17:29:46
I'm not sure if it will help with this particular poster, however I thought to pass on to all a way I significantly reduced the perceived noise of my PC tower: I moved it from on top of my solid wooden desk to underneath it, on a floor mat. Other than possibly needing to buy extension cords for the keyboard, mouse etc. (I luckily can just squeak by without them, but some of my cords are right at their limits), this simple, fast modification is free to try! 

People with less solid and dense desks that are more open than mine (where my legs/feet go) may not benefit as much as I do from this, other than the added travel distance of the sound waves causing some attenuation, however I highly recommend giving it go to all with noise issues. [Heavy padding of this open box area would possibly be even better still, but I found the amount of noise reduction from this simple step to be within my comfort zone.]
Title: Noise from "silent" PC
Post by: washu on 2012-10-16 17:31:56
Washu - are there any motherboards you could suggest? My DAC (Weiss DAC2) doesn't do USB - it has firewire, XLR, RCA and toslink.

The problem with replacing the motherboard is the power supply.  Most motherboards, even mini-ITX ones will need a normal ATX power supply and not a 12V brick.  You can use a pico-PSU with your 12V brick to make it into a normal ATX supply.

Also, a different motherboard doesn't guarantee that it won't also have the same problem.  Jetway is more on the mid to low end of the quality scale, so an Intel or ASUS board may do better. 

Toslink would be my choice for the least possibility of noise.  No ground issues and very little power draw compared to firewire. 

Here is an example of a board with a Toslink out.  Not specifically recomending it, but it might work better for you.  It does lack VGA video, so that may be an issue depending on your display.
http://www.intel.com/content/www/us/en/mot...rd-d2700dc.html (http://www.intel.com/content/www/us/en/motherboards/desktop-motherboards/desktop-board-d2700dc.html)

Quote
I couldn't find anything about C1 etc powerstates in the BIOS.

Look for anything relating to CPU power saving.  However, an Atom CPU uses so little power that I would doubt it makes any difference.
Quote
Would getting a better power supply help?

Maybe, if the 12V comming out of the brick is noisy it could cause issues.  I've had bad power supplies cause noise in analog computer audio, but I haven't encountered the issue in a while.
Quote
Or a power regenerator such as from PS Audio (http://www.psaudio.com/products/power/pw-power-plants/p10-power-plant/).

Almost certainly no, it would not help. 
Title: Noise from "silent" PC
Post by: Nick.C on 2012-10-16 18:36:51
Outside possibility: where is your modem / router / network switch in relation to your PC?

I ask as mine used to be next to my desk and caused a really annoying interference - until I moved it further away....
Title: Noise from "silent" PC
Post by: extracampine on 2012-10-16 20:19:54
My router is in a different room to the PC, connected via ethernet cable.

Re: power supply - what is the difference between an "ATX" supply and a "brick"? Is one better than the other? If I use a pico-psu with the external power supply, would this help with the problem of the DC-DC converters on the motherboard?
Title: Noise from "silent" PC
Post by: washu on 2012-10-16 20:42:07
An ATX power supply is what most non-laptop computers use for power.  It takes AC input and supplies several voltages that computers need; +12V, +5V, +3.3V and -12V.  They connect to the motherboard using a standard 20 or 24 pin connector along with usually a dedicated 4 or 8 pin connector for the CPU.  A good quality one can have very good regulation with very stable output.  Even with these multiple voltages, all modern motherboards have DC-DC converters for supplying other voltages that things like the CPU need.

A "brick" in this context is an external power supply that usually supplies only one voltage, +12V.  The rest of the voltages must be generated from the +12V, in your case your motherboard does it with extra DC-DC converters in addition to the ones normal motherboards have.  My hypothesis in regards to your problem is that those extra DC-DC converters on your motherboard are causing the noise and are of lower quality then found in a good ATX power supply.

A "pico-PSU" is a special DC-DC converter that takes the +12V from a brick instead of AC and then generates the rest of the voltages that a normal ATX power supply would create.  It is basically the same as the extra DC-DC converters your motherboard has, but designed to plug into normal motherboards that lack them.  They are hopefully of somewhat better quality, I have a couple and they make no noise that I can detect.

Your motherboard is different then most and expects only +12V from a brick.  It in fact cannot use a normal ATX power supply (without some hacking) or a pico-PSU.  It does not have the connectors needed to hook up a normal computer power supply.  My comment about the pico-PSU was for use with a replacement motherboard that has the normal connectors.  You could use any normal ATX power supply with a normal motherboard, but your small case limits the size so a pico-PSU would fit.

Title: Noise from "silent" PC
Post by: scuzzy1 on 2012-10-16 21:58:25
Would it be possible to return the computer for (preferably) a refund or replacement?

Just my opinion, but while the enclosure looks pretty roomy, replacing motherboards (and likely other components) in that small of an enclosure, can be surprisingly difficult if you have no experience with building a computer.
Title: Noise from "silent" PC
Post by: nagual on 2012-10-17 13:18:18
I recommend to anyone who desires to lower PC noise floor:

http://www.pcmus.com/power-grounding.htm (http://www.pcmus.com/power-grounding.htm)
Title: Noise from "silent" PC
Post by: pdq on 2012-10-17 13:27:00
Why are some people misunderstanding the OP's problem? This is not an issue of noise in the audio output of the PC, the PC itself is emitting audible noise from within the case.
Title: Noise from "silent" PC
Post by: extracampine on 2012-10-19 14:00:11
I asked Andrew of Small Green Computer for a refund or replacement though he did not oblige.

Interesting board washu, I'll take a look into that. I might look into trying a different brick power supply, though I don't imagine that it will make much difference.

Title: Noise from "silent" PC
Post by: garym on 2012-10-19 14:03:53
I asked Andrew of Small Green Computer for a refund or replacement though he did not oblige.


I suspect his view was that your perception of a problem is not actually a reasonable problem. Don't know.  But I can add that I've purchased three regular "vortexbox appliances" to act as music servers from Andrew. These don't need to be quiet because they are not in the listening room. On on 6TB unit I had some problems and he was very attentive to getting them solved at no cost to me, long after I had purchased.  So I've had excellent dealings with Andrew and Small Green Computers.
Title: Noise from "silent" PC
Post by: scuzzy1 on 2012-10-19 17:34:05
That's too bad about the refund/replacement.

You could try airing your issue on the silentpcreview forums. The members there go to extremes to build silent computers. Someone there may have experienced a similar problem.

If you decide to replace the mobo:

From the manual for your case, any mini-ITX motherboard should fit, though you should check the measurements of whatever board you decide on before purchase, just in case. Try browsing a site like Newegg to see what's available (look under Computer Hardware>Motherboards>Motherboard / CPU / VGA Combo>Form Factor : Mini ITX). I think for just about any board you purchase you'll need to buy DDR3 memory, since DDR2 use has been pretty well phased out. You'll also need to buy a power supply; the best (only?) option would be a PicoPSU.
Title: Noise from "silent" PC
Post by: krabapple on 2012-10-19 17:42:03
Can you record the noise from your listening position, and send it to Small Green?  That might convince them that it's a 'reasonable problem'.  ( I would think *any* computer noise audible from the normal listening position would be a reasonable problem if you've spent money to have a box built to 'computeraudiophile' specs  -- a questionable idea in itself, given some of the TOS8 violations computeraudiophile.com touts, but that's another thread....)
Title: Noise from "silent" PC
Post by: extracampine on 2012-10-20 18:45:45
I can try and record the noise, though as it's quite feint/high pitched, it might be difficult to capture!

I'll check out the silent PC forums, maybe they can help!
Title: Noise from "silent" PC
Post by: Rotareneg on 2012-10-20 20:52:11
You mentioned the "system beep." If there's a speaker hooked to the motherboard you might try disconnecting it on the off chance it's the source of the noise.
Title: Noise from "silent" PC
Post by: zenpmd on 2012-10-21 07:34:34
I had exactly this problem! But there is a solution! Its basically changing the software settings out power supply management and is completed as follows:

Its all very weird, but this stopped the (capacitors, I think) sound:

1. Execute: "regedit"
2 .Locate: HKEY_LOCAL_MACHINE \ SYSTEM \ CurrentControlSet \ Control \ Power \ PowerSettings \ 54533251-82be-4824-96c1-47b60b¬740d00 \ 5d76a2ca-e8c0-402f-a133-215849¬2d58ad
3. Change Attributes from 1 to 0.
4. Then, through the control panel - power - in the settings mode select power management processor. There will be an option disabling idle processor and high pitched noise immediately disappears.

Taken from this thread:

http://www.tomshardware.co.uk/forum/292 (http://www.tomshardware.co.uk/forum/292) ... oming-area
Title: Noise from "silent" PC
Post by: Porcus on 2012-10-21 15:30:41
By the way, what do you use this Firewire port for? The sound card?
Title: Noise from "silent" PC
Post by: extracampine on 2012-10-21 21:04:21
Thanks zen, I will try that shortly!

What do I use the firewire port for? Read above and you will see. To recap, I use it to connect an external DAC. The music is output from the PC to the DAC via firewire, and then from DAC to the amp to the speakers.
Title: Noise from "silent" PC
Post by: Porcus on 2012-10-22 00:23:53
What do I use the firewire port for? Read above and you will see. To recap, I use it to connect an external DAC. The music is output from the PC to the DAC via firewire, and then from DAC to the amp to the speakers.


Sorry: Do you have to use Firewire? That DAC accepts other inputs. If the computer becomes noisy with the firewire working, ... ?

(Doesn't seem like you got a good deal, so I am not attempting to blame the victim.)
Title: Noise from "silent" PC
Post by: RonaldDumsfeld on 2012-10-22 12:01:09
Quote
Firewire?


I don't know if it's the cause of your troubles here mate but you need to be aware that Firewire cards are notorious for causing problems among the PC digital pro audio community.

Firewire is an Apple adaptation of the old SCSI file access system. SCSI was regarded as technically superior but expensive to implement which meant it lost out to PCI/USB 2. At one time, pre Windows Vista, most users of high end DAW applications only considered working on Macs. When more users migrated towards PCs it was discovered that not all Firewire implementations were created equal. There are subtle difference in the firewire cards from different manufacturers. This had never come to light for Mac users as all Macs use the same manufacturers cards. So it's easy to test. PCs on the other hand offer an almost infinite variety.

The whole issue is now shrouded in myth and confusion as the interface manufacturers blamed the firewire cards and the card manufacturers said it wasn't their fault that the drivers offered were such rubbish. The usual recommendation (which may or not be true now if indeed it ever was) is to buy an after market firewire card with a TI chip.  That said I run firewire on a MOTU Ultralite (notoriously poor driver support) from an ASUS board with the dreaded VIA chipset and do not have issues. So.....

If you visit the website of your interface device or most popular forum you will almost always find a stickied thread  which will recommend cards which are known to work.

The above is one of the reasons why take up of the, technically inferior, USB by users and manufacturers of audio interfaces was so rapid although it now appears that Intel's USB 3.0 implementation is not 100% back compatible with USB 2.0. Specifically isochronous audio transfer. As you might expect once again Intel points the finger at the manufacturer's drivers and the manufacturers accuse Intel of not following the defined standards.

If you can afford it always buy an audio interface from RME. They always manage to get them to work.   

 

Title: Noise from "silent" PC
Post by: Porcus on 2012-10-22 13:27:11
although it now appears that Intel's USB 3.0 implementation is not 100% back compatible with USB 2.0. Specifically isochronous audio transfer.


... ewww? :-/
Title: Noise from "silent" PC
Post by: RonaldDumsfeld on 2012-10-22 15:11:48
Quote
.. ewww?


I own MOTU, NI & M-Audio nterfaces.

Forums for all sites currently report users experiencing difficulties plugging USB 2.0 devices into USB 3.0 slots when they are supposedly backwards compatible. I cannot vouch for the accuracy of these reports or the suggested explanations. Haven't experienced the problem personally, I don't have USB 3.0 h/w yet.

I'm following the situation closely because I want to buy a small portable and all the best new ones no longer come with USB 2.0 ports at all.
Title: Noise from "silent" PC
Post by: Porcus on 2012-10-22 15:30:43
... might need an ExpressCard slot to get USB2 to get compatibility? :-/
Title: Noise from "silent" PC
Post by: extracampine on 2012-12-02 13:34:37
I've continued to investigate this issue and have had something of a small breakthrough! I've managed to isolate the particular component that I think the noise is coming from - but I don't know what it is or what it does! See pics below:


Title: Noise from "silent" PC
Post by: fuflo on 2012-12-02 13:48:17
seems like the regular internal pc speaker. If that's truly the case, then you would be safe by just applying some duct tape over the hole.

// also if it's just the 'beeps', try this: http://www.7tutorials.com/how-disable-system-beep-windows-7 (http://www.7tutorials.com/how-disable-system-beep-windows-7)
Title: Noise from "silent" PC
Post by: [JAZ] on 2012-12-02 13:50:39
It looks like it is the integrated speaker. The thing that "beeps" when a computer starts (well, or that it used to), and also warns when there's a problem with the hardware (like wrong RAM modules, or faulty videocard).

I wouldn't use something that would damage it, but you should be safe in making it more silent by closing the hole in some way. Desktop motherboards used to have a real speaker, and one could disconnect it if needed.
Title: Noise from "silent" PC
Post by: washu on 2012-12-02 14:47:06
Are you absolutely sure that is the cause of the noise?  As others have pointed out, that is the PC speaker and it should only make noise if it's supposed to.  It would also be very obvious and louder than any electronic whine.  Is the noise constant or does it only present after the PC has been on for a while?

If the noise is more like electronic whine then the likely suspects are the coils to the left of the speaker in your picture.

Title: Noise from "silent" PC
Post by: extracampine on 2012-12-02 14:57:58
Are you absolutely sure that is the cause of the noise?  As others have pointed out, that is the PC speaker and it should only make noise if it's supposed to.  It would also be very obvious and louder than any electronic whine.  Is the noise constant or does it only present after the PC has been on for a while?

If the noise is more like electronic whine then the likely suspects are the coils to the left of the speaker in your picture.


I am sure that it is the cause of most of the noise, and the most obvious high-pitched noise I was hearing. The noise was constant but fluctuating in intensity, depending on whether I was doing things on the PC or not. It appeared on the Windows splash screen and then just continued.

Covering the hole on the top of this component instantly removes this part of the noise. I have put some glue over the hole and that has had the same effect.

There is still a different noise remaining, but it is much less obvious. I would like to get rid of this also, and am still looking into it. I don't think it's coming from the same component but it's possible. Would it be OK to remove this component from the motherboard as a test? I'm not sure if it's soldered down or not - it might just be stuck in with pins. I also wonder if the remaining noise is coming from below the heat sink, but I don't know if there's anything I can do about that.

The coils to the left of the speaker - you mean the component immediately left of the one I mentioned - i.e. marked 1R5M?

Thanks
Title: Noise from "silent" PC
Post by: Soap on 2012-12-02 15:18:48
It's soldered.  If you motherboard doesn't have a pc-speaker header the ideal solution would be to replace the piezo with such a header - then you could connect a speaker as-needed for diagnosis purposes.


What concerns me more than the fact it's making noise is that the motherboard design is so piss-poor that the piezo is getting energized at all during normal operations.
Title: Noise from "silent" PC
Post by: washu on 2012-12-02 15:49:21
I'd suggest you get some temperature monitoring software and see what your board thinks the CPU temp is.  It could be a high temp alarm.  That's the most likely cause of a constant noise after boot on a board like this.  That doesn't necessarily mean your board is overheating, just that it thinks it is.  Is the heat sink on securely?

All the components with an "R" like the 2R2's are coils and a potential source of noise.
Title: Noise from "silent" PC
Post by: JJZolx on 2012-12-02 16:36:01
Pair of wire snips. Should take you about 8 seconds.
Title: Noise from "silent" PC
Post by: mzil on 2012-12-02 16:49:55
When I put my finger on this component, or more specifically, cover the small hole on top of it, the main part of the noise is gone!

I'm thinking the noise problem is not due to a spurious electrical signal entering the electrical connection of that little "beep only" speaker, but rather a physical coupling of an unintended, high frequency vibration of that entire circuit board, which is being manifested by the only part which is designed to excite air, the thin diaphragm inside that component's hole. The fact that it is an electrically connected loudspeaker is just a coincidence. Although it seems as if "I press my finger against the hole and the noise is trapped", what is really happening, at least partly, is the added mass of your finger changes the frequency of resonance (mistakenly called by most the "resonant frequency") and damps the vibration/sound.

Whizzer cones on cheap (car) speakers, a primitive but partly successful "2-way" speaker design, employ a similar principal called a "mechanical crossover". They are coupled loosely to the surface below, the main cone and voice coil bobbin, through compliant glue and are meant to vibrate at a higher frequency than the heavier (more massive) underlying body, the main cone, is capable of.

I muffled the sound of my kitchen timer by stuffing a thin cone of Mortite (similar to clay) deeply into that same hole, making it a point to press against the thin internal diaphragm to help dampen its vibration. It works well for me.
Title: Noise from "silent" PC
Post by: Glenn Gundlach on 2012-12-02 20:17:31
Pair of wire snips. Should take you about 8 seconds.


Assuming you don't break anything. Stressing holes in a PCB can tear internal layers and since we don't know what is internally connected we can't know what the potential damage might be. A GOOD soldering iron and someone who knows how to use it would be best.

Title: Noise from "silent" PC
Post by: extracampine on 2012-12-02 21:55:29
Replace the piezo - you mean replace this particular component (AC-1205G) ? The motherboard is a Jetway NF96FL-525-LF, as recommended by Chris Connaker of the Computer Audiophile site.

Re. the CPU temperature - I downloaded Core Temp and it tells me that Core #0 is min 34 max 44 degrees C, and Core #1 is min 36 max 46 degrees (under mild load - about 10 minutes of playing music through Foobar). I can't imagine that the noise is a high temp alarm, or any sort of alarm, since it's (relatively) quiet and doesn't sound like an alarm, more like fizzy tinny noise. The heat sink seems to be screwed down pretty tight.

Re. the snip/soldering iron - you're saying to remove this particular component (AC-1205G)? Would this be ok to do? Wouldn't there be a "gap" in the electrical signal then?

Thanks
Title: Noise from "silent" PC
Post by: Soap on 2012-12-02 22:50:12
Replace the piezo - you mean replace this particular component (AC-1205G) ?

Yes.
Wouldn't there be a "gap" in the electrical signal then?


No.  Is there a "gap" in the electrical signal when you unplug a normal speaker?
Title: Noise from "silent" PC
Post by: extracampine on 2012-12-02 23:15:42
I don't know as I haven't done that before, but I'm assuming from your answer that there isn't!
Title: Noise from "silent" PC
Post by: extracampine on 2012-12-03 13:54:52
I just looked into desoldering components, and I wonder whether (with my limited expertise) the risk is not worth it (as the main part of the noise is now gone). Is it possible to "bypass" a component, e.g. by creating a connection between its terminals?
Title: Noise from "silent" PC
Post by: Soap on 2012-12-03 14:50:59

You don't need to get fancy on the desoldering for a through-pin item like that.  Not to say the procedure is w/o risk.  All you need to do is heat the pins enough that you can pull the component out and then ensure you haven't created a solder bridge.

You do not want to simply bridge the terminals.

As to if it is "worth it", that is completely your call.
Title: Noise from "silent" PC
Post by: Porcus on 2012-12-03 17:55:46
What about chewing gum?
Title: Noise from "silent" PC
Post by: extracampine on 2012-12-03 19:36:44
You mean stuck over the component ? Might be worth a try i guess!!
Title: Noise from "silent" PC
Post by: Porcus on 2012-12-03 21:16:43
Over and down into the hole.
Title: Noise from "silent" PC
Post by: JJZolx on 2012-12-03 21:20:59
If you do that, be sure to keep an eye out for both smoke and flames. Don't leave the system unattended.
Title: Noise from "silent" PC
Post by: extracampine on 2012-12-03 21:23:15
See above - I've already used glue to that effect - I mixed up some Araldite type glue and covered the hole with it. This got rid of the main component of the noise, though there is still a lesser noise that I would ideally like to remove!
Title: Noise from "silent" PC
Post by: Glenn Gundlach on 2012-12-04 08:19:09
I just looked into desoldering components, and I wonder whether (with my limited expertise) the risk is not worth it (as the main part of the noise is now gone). Is it possible to "bypass" a component, e.g. by creating a connection between its terminals?


If the noise is gone, thank the PC gods and DO NOT create shorts on the motherboard. It may not cause damage but it's much better to not experiment. Personally, I'd put a dot of hot glue over the hole in the noise maker. It would quiet it dramatically and clean off with a hair dryer if needed.

Title: Noise from "silent" PC
Post by: Porcus on 2012-12-04 17:14:43
See above - I've already used glue to that effect


Ah, mea culpa, I thought you were merely considering it.

I personally would have thought twice before soldering on a motherboard. Actually, before doing that I would have checked if I could cut off the component (breaking its legs without touching the mobo itself). But even before that: what about thick tape of the type used to glue photos to albums etc.? http://www.bosstapes.com.au/2108.jpg (http://www.bosstapes.com.au/2108.jpg)
Title: Noise from "silent" PC
Post by: extracampine on 2012-12-04 17:44:21
More great replies, thanks!

The glue has removed the main part of the noise, but there is a lesser residual noise (as long as the firewire DAC is plugged in). This residual noise is probably not audible from the listening position unless the room is in complete silence (rare with fridge in kitchen, occasional cars, boiler, etc), though being a perfectionist I would ideally like to remove this also!

I tried to remove the component by heating the pins, though even when trying to touch the solder itself with the soldering iron directly (there isnt much solder around the pins) I couldnt seem to get the solder to melt or the component to move. My soldering iron is 18w so I guess its possible that I need a more powerful one.

Clipping the pins as mentioned above would seem easier and less prone to accident - would this be ok and not compromise the integrity of the circuit? I would need an extremely tiny clipper to get underneath the component to clip the pins though! I'm not sure tape would be insulating enough and furthermore would introduce foreign body into the machine interior.
Title: Noise from "silent" PC
Post by: Soap on 2012-12-04 20:25:31
Clipping the pins as mentioned above would seem easier and less prone to accident - would this be ok and not compromise the integrity of the circuit? I would need an extremely tiny clipper to get underneath the component to clip the pins though! I'm not sure tape would be insulating enough and furthermore would introduce foreign body into the machine interior.


I hesitate to recommend that someone I don't know do this, but (be warned).

That piezo-electric speaker is (very likely) nothing more than a flat metal membrane with the piezo bonded to the bottom, and two leads.  All this inside a hollow, thin-wall, plastic case.

I have removed very similar ones (from my UPSs) where back-of-the-board access was problematic by squeezing the plastic body with slip-jaw pliers until the body shatters, then clipping the exposed pins.

Dirty dirty hack, but no damage done to the board.

But why not just fill the hollow plastic body with glue?  It will absolutely silence the piezo.  Any other noise is a different concern.
Title: Noise from "silent" PC
Post by: extracampine on 2012-12-04 20:54:57
Removing the component completely would rule out the remaining noise being due to it. Filling it with glue, although likely removing the noise, may leave the the possibility. I have already covered the hole with glue, so would need to remove this somehow to get more glue into the hole!
Title: Noise from "silent" PC
Post by: Porcus on 2012-12-04 21:19:58
Is the noise still there if you hold that thing firmly between your fingers? If there is still noise, and you don't feel any vibrations ... then maybe use your ears to locate some other source?

But ... put the thing in a padded box, I'd say.
Title: Noise from "silent" PC
Post by: extracampine on 2012-12-04 21:53:27
Yes, the noise is still there if i do that. Ive tried to locate the other source but as the components are so small its difficult!
Title: Noise from "silent" PC
Post by: extracampine on 2012-12-14 20:18:17
I had exactly this problem! But there is a solution! Its basically changing the software settings out power supply management and is completed as follows:

Its all very weird, but this stopped the (capacitors, I think) sound:

1. Execute: "regedit"
2 .Locate: HKEY_LOCAL_MACHINE \ SYSTEM \ CurrentControlSet \ Control \ Power \ PowerSettings \ 54533251-82be-4824-96c1-47b60b¬740d00 \ 5d76a2ca-e8c0-402f-a133-215849¬2d58ad
3. Change Attributes from 1 to 0.
4. Then, through the control panel - power - in the settings mode select power management processor. There will be an option disabling idle processor and high pitched noise immediately disappears.

Taken from this thread:

http://www.tomshardware.co.uk/forum/292 (http://www.tomshardware.co.uk/forum/292) ... oming-area


Zenpmd - somehow I managed to overlook your post before, and found it just now.

I would like to say - thanks!! After changing this power setting as you describe, it has gotten rid of most of the remaining noise!! There is a little bit left, but it's even quieter and definitely not audible from the listening position. What was causing this noise that disappears when this setting is changed?