The Specs

The specs

Tile-based rendering architecture
8-layer multi-texturing
Internal true color
Twin high performance texturing pipelines
Full triangle setup
Bilinear, trilinear, and anisotropic filtering
Full-scene anti-aliasing (2x and 4x super-sampling)
Environment-mapped and DOT3 bump mapping
DXTC and S3TC texture compression supported
128-bit SGRAM/SDRAM interface (16 to 64MB supported)
175MHz core/memory clock
0.18-micron manufacturing process
15 million transistors
300MHz RAMDAC

Notes

By shifting from ST's older 0.25-micron manufacturing process to its smaller 0.18-micron design, ST was able to raise the clock speed of Kyro II to 175MHz (up from 125MHz). With its faster core, Kyro II matches the clock speed of NVIDIA's original GeForce2 MX, but trails GeForce2 MX 400 by 25MHz. Since the core clock and memory clock are synchronous, Kyro II actually offers more memory bandwidth than both the GeForce2 MX and GeForce2 MX 400, which operate at 166MHz. While NVIDIA's GeForce2 MX/MX 400 offer 2.7GB/sec of bandwidth, Kyro II offers 2.8GB/sec. In comparison, ATI's similarly priced RADEON 32MB DDR offers 5.87GB/sec of bandwidth thanks to its 183MHz DDR memory. If you keep in mind the Kyro II's tile-based deferred rendering (TBR) engine, we'll see that Kyro II's 2.8GB/sec of bandwidth is plenty to keep up with, and in many cases outperform RADEON and GeForce2 GTS in real-world situations, both of which offer over twice as much bandwidth on paper.

While memory bandwidth is an important part of the equation (especially at high resolutions), fill-rate is also important. With the Kyro II's 175MHz core and twin pixel pipeline, the Kyro II offers a fill-rate of 350Mpixels/sec. Since its only capable of processing a single texture per pixel in a clock cycle, the Mtexels/sec fill-rate is 175Mtexels/sec. Initially, these fill-rate numbers look unimpressive in comparison to GeForce2 MX and especially RADEON, but keep in mind, yep, you guessed it, the Kyro II's unique TBR approach. While traditional cards calculate three (and sometimes more) times more data than necessary (overdraw, remember?), Kyro II processes exactly what's needed there is no overdraw. In essence, while the traditional architectures peak numbers are all theoretical, Kyro II's fill rate figures are effective numbers. We tested this statement in Serious Sam which tests real-world fill rate performance. Sure enough, Kyro II offered 100% of its claimed fill rate in both single texture and multitexture tests.

Keep in mind that the amounts of overdraw varies from scene to scene, and from game to game. It's a complicated issue that can't be summed up easily, but clearly it's impressive to see a product that delivers on its numbers.