Notice how my CPU is not maxing out at 100%...It is odd since SC2 is CPU intense. And on the left my GPU average is below 100% as well. I currently have two ATI Radeon 6870's in crossfire w/ an AMD 955 black edition.
Will any other information help decide whether I need a new power supply?
SCII is very CPU intensive, but only on two cores, which is why you only ever hit about 60% usage, 50% comes from SCII the rest come from windows tasks. Your GPUs look like they were reasonably close to 100% load which is good considering that SCII is usually CPU bottlenecked.
Its unlikely that your power supply is limiting your performance, it doesnt usually cause things to throttle it generally just shuts itself down.