It's been a while in coming, but ATI's response to NVIDIA's impressive GeForce 7800 boards is now upon us. R520, the codename for their high-end part, has been much talked about for a variety of reasons, from speculation as to its performance and number of pipelines to conjecture as to the reason for the delays in bringing this part to market. All of that can now be put behind us (although we're still left waiting to see just how good availability of retail boards will be), as the technology is now laid out on the table for all of us to see.

In this article, we'll be taking a look at the architecture which powers all of ATI's new Radeon X1000 series of parts, and the cores that power them - R520 at the high-end, RV530 in the mid-range and RV515 at the low-end.