I don't know what calculations he's talking about reload, but the values you listed seem a litte weird. You should be able to get a decent power supply that can do 30amps on the 12V rail(s) for under 200 easy.
You'd have to hunt for a brand name you like but just one example I found on new egg has 4 12 volts rails each able to source 18 amps (that's 72amps, hopefully I didn't miscalculate it for $110
Ah, I get it now, here is what I said:
A good well built switching PSU for 12 volts only capable of 30 amps typically runs over $200 USD so go figure.
When I said well built switching PSU for 12 volts only I was getting at or referring to non-ATX power supplies that are American built, nothing to do with ATX PSUs but commercial power supplies like some of these. The Cosel model PAA33F-12 is a 12 volt 27 amp power supply. That supply meets or exceeds a variety of safety standards as well as EMI compliance standards. The thing has a price tag around $482 USD. There are plenty of similar ones out there in the $350 range lacking the DC input features. Sorry for any confusion on what I was getting at.
So yes, you can buy a cheap ATX PSU for $29.95 or an expensive ATX PSU for over $100 or so USD that deliver well in excess of 30 amps on the 12 volt rail(s) but those were not what I was getting at. My bad on any induced confusion factor.
Ron