The focus of ATI roadmap is to get the RV 670 as fast as they possible can and to take some of the Xmas market from Nvidia and after that the company will start focusing on shrinking the mainstream and entry level chips to 55.

ATI's RV630 is now 65 and has quite good dissipation but the RV635 the 55 nanometre version of the same chip will be even better.

The RV620 is the 55 nanometre of RV615 and both of these new chips will launch in early 2008. Nvidia won't have the $99 65nanometre part and the company is not even close to shrink to 55 nanometre.