I have been looking at the new 7950's for my new build. The reference card has one fan. But then XFX has two fans on both of their models. Gigabyte has three fans on theirs. Are extra fans really necessary? I understand that the ones with more fans are generally overclocked, but can you overclock a stock reference card without extra fans, or are you asking for trouble keeping just one fan? I was thinking about starting out with two 7950's crossfire in a three monitor eyefinity setup, I don't think I will need to mess with overclocking, but I am just curious. Thanks