YUP, 3DFX was a third video chipset company which released its Voodoo Graphics chip in 1996 through 2000. It was an OEM supplier for graphics card companies, which designed, manufactured, marketed, and sold their own graphics cards including the Voodoo chipset. I used to love the cards. I'm now giving away my age.
At the time they were the fastest, most powerful chipsets on GPU's in the market until around 1999. They were the first to bring the idea of SLI to the market. Before Direct3D and OpenGL they created GLIDE, also kind of like Physx implementation for developers. OpenGL was created shortly after and they supported both GLIDE and OpenGL on their chipsets.
STB Technologies, which was one of the larger graphics card manufacturers at the time bought them out; the intent was for 3dfx to start manufacturing, marketing, and selling its own graphics cards. Prior to that they would only create the chips that other manufacturers would put on their PCB's. They had series called Voodoo Rush, Voodoo Banshee, Voodoo 1, 2, 3, & 4.
Example of Voodoo 4 series had these specs Voodoo 4 166 Core/ 166 Memory, Fill rate pix 333 / Fillrate tex 333, 128-bit 32 SD MiM with AGP 4x/PCI slot.
Through poor management of the company they began to spiral down, no fault of their products but the people running them. In 2000 Nvidia bought them out. Nvidia took over 3DFX support and shortly thereafter released GeForce 256 and GeForce 2 GTS cards and phased out the Voodoo brand. The rest is history.
Us older guys, still have a soft spot for the once great 3DFX. They really revolutionized how great gaming could actually look on computers at the time with graphics. They raised the bar and fired up the competition amongst the chip set manufacturers back then. Today we have two chipset makers left as we are all well aware of AMD (who recently absorbed ATI) vs Nvidia. Still have multiple manufacturers that use those chips on thier PCB's. MSI, ASUS, EVGA, Sapphire, etc. The last step in this heirarchy is for Intel to absorb Nvidia.