RAM-only cards exist, but they max out at 8MB because the 1200's reduced-cost 68EC020 CPU has fewer address lines than a full 68020. And if you use more than 4MB you'll lose access to your PCMCIA slot due to a not-so-great design decision concerning the 1200's memory addressing.
Accelerators with full 020s or better get around both of these problems by mapping the expansion RAM into a different area.
