The Synth of Doom mounts the PSUs upside down in the back using small
aluminum angle brackets, so that the mass of the aluminum chassis is
facing up instead of down to the wood:
http://www.hotrodmotm.com/images/case/synth_of_doom_back2.jpgMoe
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If you are using one of those typical Power One supplies where the
chassis is the heat sink, you should not screw it down directly to a
wood cabinet. You need to have some air circulation around the chassis
if you ever want to use the PS near it's rated output. The best bet is
to use at least 1/2" spacers to elevate the PS off the wood case.
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