Wow thanks for the reply but you sadly posted nothing relevant to my question.
It makes no difference to me if we talk LTC or BTC as BTC is generally 10x that of LTC.
I am not interested in single core 6870 stats as those are easily found.
I do not want to make assumptions that a dual a core is double a single. That is why I made the post.
I guess a screwed up by making the assumption that I had checked the comparison pages and found nothing that people would know I had already checked the pages you linked.
See what assuming does.
It's actually a pretty fair assumption that two 6870 GPUs would be about twice the hashrate of one, given they're clocked identically. That may not be the case (although I don't think I've ever seen a dual-GPU 6870 board), and they may be clocked slightly lower.
Since they're the same cores as the single-GPU 6870, I would say divide the hashrate in the hardware comparison list by the given clock, multiply that number by the GPU clock on the card you're getting, and double it. So long as it doesn't implode or something, that's you're best guess as to the hashrate.