Right now I am torn between a gtx 670 ftw edition, a reference 7970 to flash with the ghz BIOS, and the gigabyte windforce 7970. I have a 600w PC p & c mk III psu. Would my psu be able to handle an overclocked 7970? I only use a 1080p monitor but I want to future-proof as much as I can. Is the GE vbios really worth it over ocing a custom cooler 7970?