The first chip, the RV560, features eight ROP units and is capable of pushing out eight pixels per clock, which is double the number of the current X1600 (RV530).
The number of Pixel Shader ALUs (arithmetical logical units) will also get a boost, and the RV560 will feature 24 of them, with four Vertex Shader units. The number of Texture Memory Units (TMU's) has also been raised from four to eight, since there is no logical reason to have fewer textures than pixels per clock.
The second chip, the RV570 will truly be a mainstream monster, which should give Nvidia a headache. The chip is scheduled to have 12 ROP and 12 units (12 pixel/textures per clock), 36 Pixel Shader ALU's and six Vertex Shaders. Clock speeds are not defined, but you can expect 650 or even a 700MHz GPU clock for the X1700XT part. It all depends on yields.
ATI's 80 nanometre mainstream parts are almost certain to be named X1700, although we have no confirmation about the suffixes used for two different chips. We know that two RV570 based models are likely to be named X1700XL and X1700XT, while the RV560 will find itself in the X1700Pro range. Unless the company pulls out an X1500 moniker to differentiate the two - and it would be interesting to see X1500 outperforming X1600 by a mile. At the same time, X1300 will occupy the low-end, and the X1600 should slowly fade away to leave room for different clocked RV560/570 parts.
Inq