Ooh, we used to dream of a 256k video card. My first PC was an Atari PC3 (possibly the only XT-class machine with a 102 key layout) with CGA/EGA. Still compatible enough so I could do raster bars by sending values to port 3D8 timed with the hsync, and play samples through the motherboard speaker with timed interrupts.
Had a C64 as well, does it show? ;-)