The late 2005 model carried a 750W power supply, which is a lot, but there are PC power supplies (and many server power supplies) that are much larger.
My dual-proc server at home has a dual-800W power supply. (It's meant to be for redundancy, so it should only draw 800W max.)
My dual-proc server at home has a dual-800W power supply. (It's meant to be for redundancy, so it should only draw 800W max.)