Kelvin (microarchitecture)

Kelvin is the codename for a GPU microarchitecture developed by Nvidia, and released in 2001, as the successor to Celsius microarchitecture. It was named with reference to William Thomson (Baron Kelvin) and used with the GeForce 3 and 4 series.

Graphics features

 * DirectX 8.0 (8.1 in the original Xbox)
 * OpenGL 1.2 (1.5; 1.4 in the original Xbox)
 * Shader Model 1.3
 * Vertex Shader 1.1
 * Max VRAM size bumped to 128MB
 * New memory controller with Z compression

GeForce 3 (3xxx) series

 * NV20, 57 million transistor
 * NV2A (Xbox GPU), 57 million transistor

GeForce 4 (4xxx) series

 * Crush11, 20 million transistor
 * NV17, 29 million transistor
 * NV18, 29 million transistor
 * NV25, 63 million transistor
 * NV28, 36 million transistor
 * NV2A (Xbox GPU), 57 million transistor