As far as I know about the 11/93 (or 11/94), all memory is on the CPU module. The 11/9[3|4] is sort-of an 11/8[3|4] with all (PMI) memory on the CPU module as the cache on the 8[3|4]. The 11/9[3|4] with 2 MB RAM can only be upgraded to 4 MB by adding RAM chips on the CPU module. However, all holes are filled with solder, so this upgrade is quite a lot of work. Henk