Comes in late August
We just got a final confirmation that R700 uses two RV770XT GPUs and that it supports massive 2GB of GDDR5 memory.
Naturally, the card uses 256 bit memory interface and it looks that the card can ship in last days of August.
ATI used the codename Spartan for R700, as someone got hot for the movie. At this time, there are no talks about any clock speeds but the brand should settle at Radeon HD 4870 X2 area.
We will confirm this as soon as we can.