I have one of these as my lower card. It typically sets at 1254Mhz with no OC required, though I've upped the memory 300Mhz.
The funny thing is, the card lets you provide more power than the others (159% vs 132%), but then needs so very very much less. In SLI it will be sitting at 80-85% power, while the other card is 110-120% power, while it's clocked higher. It also sits around 15C lower than the other card. I wish I could make it the primary, but putting it in the top slot where there is no gap for a triple slot card, makes it suddenly 98C or so in furmark.
It will do somwhere between 1300 and 1350Mhz, but in SLI, it doesn't really provide any benefit to make it faster than the other. What I've seen is just that the utilization on that card goes down instead of it helping.