Hi Ncraw,
Power ( P watts) is directly proportional to current (I amps). You'll find that P=IxV so as the amps go up, power capacity increases. So for the supply you are talking about P=4x12 = 48 or around 50Watts. 10 Amp models will be around 120 Watts etc.
Allan Gould has done a review on this mount and describes it as a bit power hungry. Check it out here
http://www.iceinspace.com.au/index.p...44,288,0,0,1,0 if you haven't seen it already.
Cheers
