Quoted from Coyote:
With all the power talk, when I get home tonight - if I have the time - I am going to measure the current draw off the 5v and 12v rails on the power supply. Will post the details here. That will at least help people and let us know how close to max the *current* power supplies are being drawn. (No need to worry about the 48v supply..)
Okay, here are my findings. While I used a commercial-grade multimeter, it's intended for railroad use, so isn't calibrated to fast changes in current. (This means that there may have been some peaks higher and lower than what I have measured below, but they were short enough to where my meter couldn't or didn't read them.)
+5v Rail
3.505 amp Max
2.555 amp, all inserts/GI "Red"
2.281 amp, all inserts/GI "Green"
2.222 amp, all inserts/GI "Blue"
3.180 amp, all inserts/GI "White"
1.750 amp, all inserts/GI "Off"
+12v Rail
1.770 amp, attract mode, Backbox and Start button lit.
The max on the +5v rail occurred during bootup, likely when the computer initialized all the PRoc boards. It never got that high again while messing in the Tet Menus -> LED test.
The +12v rail was pretty steady during attract mode.
While I had the game open, I forgot to get the part number of the Mean Well power supply. However, I believe it's a +5v 5 amp, +12v 3 amp. KingPinGames can correct me if I'm wrong. This means that when peaked, the stock, game power supply only has about 1 amp worth of extra handling power on the +5v rail (to be safe).