Just a heads up, the 1 GB models unlock too, without a dual bios switch i'd suggest having an extra card handy incase you have a bad flash you can boot with the extra card, and reflash the 6950 back to stock. To unlock on the 1GB models you don't flash the 6970 bios like the 2gb models, instead you edit the stock bios to unlock shaders, if successful you can from there test voltage and clocks in windows at 6970 settings. If stable you can add those to the bios the same way.