[sdiy] OT: The best ways to silence a PC?

[ASSI]

On Saturday 10 May 2003 10:09, Glen wrote:
> This is mostly off topic, but it does affect many of the people on
> this list. It also has an impact on many people's ability to hear the
> music they make, without the annoying noise of a PC that might be
> running in the same room. Often that very same PC is instrumental in
> either creating or recording the music in question. This is also a
> DIY project--maybe this IS on-topic after all.

For some seriously DIY PC silencing a colleague of mine has done take a 
look at:
http://www.foeste.net

> What I want to do is gather together ideas of how to best silence a
> PC.

The most noise is there because you need to remove heat. So a good 
start is to use components that do not produce much of it, because that 
makes the problem of removing the heat with minimum noise considerably 
easier. Next, people tend to concentrate on fans, but forget that you 
actually need to move the air around the components you want to cool 
with a certain speed and you also need to keep the total airflow rather 
high. Air is a terribly inefficient cooling medium and at the required 
high speeds and flows it will produce quite a bit of noise all by 
itself. The computer I'm typing this on makes not much noise, probably 
around 30-35dBA - most of that is actually from the airflow itself, as 
you find out when you briefly interrupt the airflow by blocking the 
exhaust. I replaced the CPU fan with a Verax and kept the original PSU 
fan. Back at the university I've had a muffler box for my workstation, 
which basically provided forced airflow to the unmodified workstation 
inside, but controlled the turbulence noise by carefully designed 
intake and exhaust with a large diameter. A box like this would not be 
terribly difficult to DIY I reckon.

Next up are liquid cooling (see above) and heatpipes. Both are 
cumbersome to dimension, expensive and badly matched to the electronic 
components in a computer that are all designed to be air cooled. I've 
seen a DIY alcohol heatpipe for the first Alpha AXP processor at DEC 
CRL in Palo Alto while visiting a friend there a few years ago... 
Liquid cooling helps to get heat away from a few chips quickly, but the 
rest of the computer still needs airflow, especially the voltage 
regulators right next to the CPU. Nevertheless there are a few small 
companies that make computers that are cooled by heatpipes. They are 
expensive as on top of the custom made parts for cooling the PSU 
generally is replaced by a passively cooled one for industrial 
applications. But since the enclosure can be completely sealed, these 
are the most quiet computers you can get today.


Achim.
-- +<[ Q+ & Matrix-12 & WAVE#46 & microQkb Omega sonic heaven ]>+ --

SD adaptations for
Waldorf Q V3.00R1, Q+ V3.53R1, microQ V2.20R1 and rackAttack V1.04R1:
http://homepages.compuserve.de/Stromeko#WaldorfSDada