On a Chinese-based website called Chiphell, details on AMD's upcoming Radeon HD 6700 Series graphics cards broke cover, offering up pretty much every bit of detail that people would be interested in, all in an organized fashion. The new series is set to replace the Radeon 5700 series, and AMD (at least on the leaked image) says that the new series will offer up "twice the horsepower" compared to the previous chips.
The leaked image shows the range of AMD's series, from the 5700, to the 5800, and including the new 6700 series. In the breakdown, we see that while clocked speeds may not be that different from previous models, AMD says the new series will add almost a 60 percent increase to the raw computing power. Accordingly, the Radeon HD 6770 will produce somewhere near 2.3 teraflops, while the Radeon HD 5850 only produces 2 teraflops.
However, it should be noted that both of the new 6700 series models will consume more power, but they will be more efficient, when compared to the performance, versus the 5800 series of chips. As for a release date, that wasn't included in the leaked document, but it has been rumored that AMD is ready to make a launch announcement some time in October.