Radeon R100

The Radeon R100 is the first generation of Radeon graphics chips from ATI Technologies. The line features 3D acceleration based upon Direct3D 7.0 and OpenGL 1.3, and all but the entry-level versions offloading host geometry calculations to a hardware transform and lighting (T&L) engine, a major improvement in features and performance compared to the preceding Rage design. The processors also include 2D GUI acceleration, video acceleration, and multiple display outputs. "R100" refers to the development codename of the initially released GPU of the generation. It is the basis for a variety of other succeeding products.

Development

Architecture

The first-generation Radeon GPU was launched in 2000, and was initially code-named Rage 6 (later R100), as the successor to ATI's aging Rage 128 Pro which was unable to compete with the GeForce 256. The R100 was built on a 180 nm semiconductor manufacturing process. Like the GeForce, the Radeon R100 featured a hardware transform and lighting (T&L) engine to perform geometry calculations, freeing up the host computer's CPU.

With respect to the 3D hardware within Radeon, the processor can write 2 pixels to the framebuffer and sample 3 texture maps per pixel per clock. This is commonly referred to as a 2×3 configuration. Of Radeon's competitors, the 3dfx Voodoo 5 5500 is a 4×1 design and the GeForce2 GTS is 4×2. Unfortunately, the third texture unit did not get much use in games during the card's lifetime because...
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