What is Texelfx or TMU?
Voodoo Graphics ™ chipsets have two units. The first one interfaces the texture memory on the board, does the texture mapping, and ultimately generates the input for the second unit that interfaces the framebuffer. This one is called Texelfx, aka Texture Management Unit, aka TMU. The neat thing about this is that a board can use two Texelfx instead of only one, like some of the Quantum3D Obsidian boards did, effectively doubling the processing power in some cases, depending on the application. As each Texelfx can address 4MB texture memory, a dual Texelfx setup has an effective texture cache of up to 8MB. This can be true even if only one Texelfx is actually needed by a particular application, as textures can be distributed to both Texelfx, which are used depending on the requested texture. Both Texelfx are used together to perform certain operations as trilinear filtering and illumination texture/lightmap passes (e.g.
