…But like, how?? Do you plan to desolder every pin, make your own BIOS, write drivers, etc?
Looking at the photos I reposted earlier, the RAM is permanently soldered, but I have seen instances of people adding higher density chips in their place. But, the fact of the matter is that there is no support built into the firmware to make this work.
It probably would be better to find a way to flash linux to it and run a very light version of early windows in a VM. But good luck finding a way to access vex’s config files for the VEXos. IF everything else works, you could find a way to just use the micro USB, as it is just USB, but… micro. There are some off the shelf dongles and adaptors that can do this for you. I don’t know if it’s set up correctly for this use, though, as I am no PCB design expert or have access to vex’s proprietary firmware.
I love @Bubski 's rPi idea, and I have another thing to add: You could use a Pi Pico for its small size and find a way to interface it with the power distribution board in the brain and the screen. ( you’d just have to find the usage of all of those pins in the ribbon cables from the processor board to the display and the PD board.
Sidenote part 3
I’m a EOS person myself, but I guess that’s pretty typical for one who does tech theater rather than concert lighting (MA). Fun to see the two spaces collide!