Well yes i can run benchmarks at 1300mhz, but that doesn't mean its stable.
My 100% stable overclock is 1230mhz on the core and 1250mhz on the 2nd card. Not all cards are the same man even if they're from the same vendor
Now that is one beast OC.. same as my 100% overclock, but im sure you can get your memory to 1700mhz.
In this case......Nothing a fresh windows install won't fix
yeah I heard that all cards are different too. BTW I don't know it is just me or, do you feel like the graphic in game looks really bad? cuz it seems like it lack AA compare with my HD 6990 which I used to have. Also when I overclock to 1200Mhz, it start to show flikering artifacts stuff ;(