"Thanks (again) for maintaining such a great Mac resource. I recently picked up a MDD DP 1 GHZ in excellent condition but when I started it up I could immediately tell why they had been called "wind tunnels". I searched your articles (Macs/Systems page, G4 section) and found one on MDD Fan Mods from 2002. (I assume this one from 2002 on replacing PS fans - Fan Mods in a PowerMac G4 MDD Tower-Mike)
I followed those steps, using Silenx Ixtema fans, 2 x 60 mm for the PSU and 1 x 120 mm for the case, cost around $50. Noise dropped to 43 dBA. Running under heavy load the MDD CPU temp is reported at 64 degrees C, just a 5 degree increase in temp. That's with 2 SATA hard drives and a second DVD burner added to the OEM drives.
-David C."

The Macs/Systems page, G4 section has a lot of MDD related articles/cooling mods, etc., but one I liked (idea and looks) was the 'Unreal' Mirror Drive Door Tower Cooling Mod (replacing the front speaker with an exhaust fan and using an Unreal logo fan grille). Article also includes notes on replacing PS fans (with adjustable speed - although I'd not go too far with that option).

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