Are we assuming that Chip Chase, a genius technohead with regular access to alien computers and the gregarious aliens in charge of same, never had any upgrades made to his personal home workstation?
With current cutting-edge lab tech, we should be able to squeeze about 100 terabits into a volume the size and shape of a 5.25-inch floppy dish. That might be enough to encode a compressed version of Prime - and that's assuming that Cybertronian tech was only 25 years ahead of 1980s-era humanity.
Another assumption, one I like a little better, is that the floppy disk didn't contain Prime himself - it contained a three-megabit key sequence which would unlock an access channel to the Allspark via the Matrix and find/retrieve Prime's actual pattern. Or it encoded precise time-space co-ordinates for a read-only timescoop to find/copy an older version of Prime's laser core, plus a fractal sequence which would act on the timescooped data to create a rough outline of events from the timescooped point to the moment of disk encoding.
In other words, anything can be technobabbled away.![]()