The Fairchild Channel F, released in 1976, was the first modern game console, in the sense of being the first one to accept games as software, rather than just modular configuration switches.
Looking at the specifications, the thing that jumps out at me is that (in addition to 64 bytes of working RAM) it has a 2K write-only frame buffer:
The above both directly describes the frame buffer, and gives the resolution, from one which one can verify that 128x64x2/8 = 2K.
This is particularly notable in that the Atari 2600, released a year later, did not have a frame buffer.
How did Fairchild provide such a thing within the technology and cost constraints?
Looking at the ads in the back of Byte magazine for December 1976, I don't see any chips advertised for any price that could easily provide that. There are e.g. 256x4 static rams advertised, but it would take 16 of those to make 2K, which would surely blow the budget, and looking at photographs of the circuit board, I don't see any large arrays of identical chips.
So how did they do it? What chips were used?