...You're all doing it wrong...
Answer:
http://forums.benheck.com/viewtopic.php?t=18044
I personally wouldn't mess with that line. It powers the CPU, GPU and probably RAM as well. A CPU's voltage shouldn't be adjusted by even a fraction a a volt unless you know what you're doing... like if you're trying to overclock it or something.
Yes, the 12V is for audio and audio only, and does NOT take 12 watts. Dunno where that figure came from.
No, the DVD motor uses the 5V line... as well as the rumble motors in the controllers. From what I've found in my field-tests, the 5V line could even be cut off and the GC wouldn't suffer from it as long as it wasn't trying to load something off the disk; I did it.
Oh, and Digikey surely has what you need... is there a problem with using Digikey?