The power supply won't have issues unless you have an ADC display. The trickle power for the power button on it heats up the power supply but if the unit is off, the fans don't spin. You have to kill the power to the power supply if you use such a display if you shut it off or sleep it. Both my dual 1ghz MDD's run 60 degrees on the CPU, I never sleep or shut them off and they keep chugging. The one that's been running longer has 4 hard drives and a 9800 Pro video card as well. By the looks of your pictures you're going way overboard. The best thing you should do is add two small fans in the front hard drives and zip tie two more behind the CPU between it and the casing. The ones in the front should pull air in and the ones on the back should pull air out.

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