Alright guys, I've got them. I measured the mA draw for each individual voltage in the Gamecube. For testing, I used SSBM, Soul Caliber II and Super Mario Sunshine. The difference between games was small... too small to keep separate records of. The following measurements are the lowest to highest ratings I saw at any given moment during measuring. This means that it never dipped below or went above the ratings I gave. Here they are:
1.9V = 1800mA - 2300mA
3.3V = 700mA - 900mA
5.0V = 300mA - 400mA
12V = 4mA - 5mA
The 1.9V line never went above 2100mA during gameplay, but raises to 2300mA during power up.
<Edit by vskid
It has been found
that the 1.9V line actually draws 6000-6600mA.>
During testing, I found out that the 5V line is only used for the DVD spinner motor. It quickly dips to zero a few times when the laser is reading, and it is the only thing that is affected when the 5V line is disconnected. The 5V can be cut off as long as it's not trying to load from the disk.
I also confirmed that yes, the only thing the 12V line is used for is the audio. I accidentally shorted the 12V line to ground for about 15 seconds without knowing it, and it killed the audio (and only
the audio). I'm pretty sure it just blew a fuse on the PSU, because I was able to feed the 12V line straight from the power switch/fan board after that and the audio was fine. The 12V line was measured without
the fan being part of the circuit, for three reasons. One, the fan is feed directly from the power input, having nothing to do with the PSU (which is what I was measuring), two, the current draw is listed on the fan anyway, (It was 50mA, if it's that important.
) and three, I personally will probably be replacing it with a 5V fan on my GC laptop. Or maybe not, we'll see. The important thing is that the BOARD only takes 4-5mA. This means that only a very very small step-up regulator is needed to supply the 12V line.
I think that's all I've got for now, I hope this information is useful to you all. I've got to go clean up now, then I'm off to start designing my new power supply.