[sdiy] Not a synth question at all.... (but it is about diy and sound! :)

[John L Marshall]

I have two computers. Both are rack mounted. While assembling the computers 
I listened for noise sources. Here is what I found and did:

Most rack mount computers have a door and air filter on the front. Many 
racks have doors on the front.

Thin copper is a better heat conductor and radiator than aluminum for the 
CPU heat sink therefore a smaller fan is required. I wired a resistor in 
series with the fan to slow it a little. That made a big difference in the 
noise level from the fan.

I found that Enermax power supplies are quieter than others.

I found that the IBM hard disks were quite noisy. I replaced them with 
drives with a low noise rating.

Rack mount computers have front panel, internal and backpanel fans. Not all 
of the fans are necessary. Many Setup programs have a page for monitoring 
system temperature. I noted the CPU temperature and internal temperature 
then started turning fans off. I disabled the front panel fans. I disabled 
the backpanel fans. When I disabled all fans except the CPU and power supply 
the temperature went up. I wired the two internal fans in series and 
temperature went back to the same as when all fans were running.

I use a basic video card; no heatsink or fan.

Remove the extra plug-in cards that you are not using. Take the sound card 
out. Use an external Firewire or USB analog I/O interface. Do you really 
want A/Ds and D/As in that noisy computer environment?

Remove the internal peripherals that you are no longer using. When is the 
last time you used that Zip or Jaz drive? Or that floppy?

Use clock throttling, if available.

Use thermal throttling, if available.

Turn off all unnecessary TSRs.

Take care,
John
www.sound-photo.com
www.antenna-farm.com

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