I assume he meant EVGA. They’re a hardware company that used to manufacture graphics cards designed by Nvidia but exited the GPU market because of unfavorable contract conditions eating into their profit margins.

Plenty of other third-party manufacturers exist like Sapphire, XFX, PowerColor, Zotac, ASRock, Inno3D, Colorful, MSI and ASUS.

As for the main companies that design (and also manufacture) GPU’s: AMD, Nvidia and more recently Intel.