13.3.2. What is a geoRAM Unit?, When Commodore REUs became hard to find several years back, Berkeley Softworks introduced geoRAM, which is a 512K RAM expander. This RAM expander gives you all of the advantages of a 1750 with GEOS. However, it is not 1750 compatible, so it will not work like a 1750 outside of GEOS; it is transparent to other programs. (As a caveat on this, see the info on RAMLink)). DesTerm128 2.0 will not work with a geoRAM plugged in. A special version of GEOS 2.0 (which is bundled with geoRAM) is necessary to use geoRAM. No additional power supply is necessary to use geoRAM., COMP.SYS.CBM: General FAQ, v3.1 Part 8/9