You can see in the pics crazyates posted that we're using an IBM 2000w PSU. Three delta fans on the side keep it nice and cold without having to open the case. 1 PSU feeds 4 AntMiners nicely.
As far as hot wires, we had an AntMiner on the test bench running on a 750w ATX PSU but had a cheesy molex to PCIe adapter that ended up putting all the load onto just 1 pair of about 18awg wire. When we noticed hot cables and the yellow turning brown, we moved to the correct set of cables (PSU is modular). Not only are the cables now running nice and cool, but it's also pulling 30watts less from the wall!!!