Graphic card for new gaming rig

[mosbius]

APPROXIMATE PURCHASE DATE: December 2012

USAGE FROM MOST TO LEAST IMPORTANT: Gaming(Guild wars 2, WoW, LoL, SC2, BF3), Watching movies.

CURRENT GPU AND POWER SUPPLY: None, will be getting a Cosair HX850 for PSu.

OTHER RELEVANT SYSTEM SPECS: I will be getting a i5-3570k on the Asus P8Z77-V PRO with 8gb of RAM and getting the Cooler Master Hyper 212 EVO for cooling.

PARTS PREFERENCES: Either the gtx 670 or HD 7970

OVERCLOCKING: Yes

SLI OR CROSSFIRE: Yes

MONITOR RESOLUTION: 1920x1080

ADDITIONAL COMMENTS: I am considering getting either the gtx 670 or HD 7970 however am unsure which one to get. Please if possible also suggest a manufacturer for the card for me. Thanks in advance!

 

[mactronix]

There really is not a lot in it between those two cards. I would be looking at price and bundle and extras thrown in like Game coupons and guarantee periods to decide.
However without looking all that up my personal preference would be this

http://www.techpowerup.com/reviews/ASUS/GeForce_GTX_670_Direct_Cu_II/33.html

Mactronix