The card we were loaned to preview was not a final production board, and the drivers that were supplied were not final code. That said, the specifications of the board are pretty much etched in stone, and the performance should be very near to what should be expected from the final product.

All of the Hercules 3D Prophet 4500's manufactured by Hercules will ship with 64MB of SDRAM. At the moment, Hercules is positive that they can have all shipping boards running at 175/175MHz, though we did see samples running at 166/166MHz. The suggested retail price will be $149, though we would assume many of the larger distributors would be offering the product for less than that. If TV output is of importance, Hercules will be marketing a variant of the 4500 mated to Chrontel's TV-out chip for $169. DVI-I support will be another possibility thanks to Silicon Image's output chip.

For the even more frugal customer, Hercules will also be offering a board based on the original KYRO, called the 3D Prophet 4000. Equipped with 32MB of SDRAM, this board will cost closer to $79.

As a side note, this arrangement does not mean Hercules has exclusive rights to the KYRO II. Judging by past products, we expect to see KYRO II based boards from both PowerColor and VideoLogic at competitive prices.

If the KYRO II only benefited from not having to texture and shade invisible polygons, the architecture would not be nearly as efficient as it is. In fact, ATI has already implemented a solution to help avoid texturing and shading polygons that are not visible with a technique called early Z detection - a test to determine whether or not a polygon is rendered before it is actually drawn.

At the heart of tile-based rendering is Display List Processing, a procedure in which the entire scene is divided into tiles with an area of 32x16 pixels. Since each tile is rendered independently, the Z-buffer data for the entire scene does not need to be stored in external memory. Rather, a small Z-buffer on the chip can hold the data for each tile, eliminating reads to the external memory and cutting down latencies associated with such accesses. This on-chip buffer continuously processes with 24-bit precision, regardless of a scenes color depth.

Using a display list, the KYRO II can utilize per-pixel hidden surface removal to analyze each tile before textures are applied. The chip possesses another buffer that allows the processor to blend textures on-chip, without having to make external accesses to the frame buffer.