The 16 Megs are DIM chips ( whatever they are. ) I seem to remeber that you could keep your existing 16Meg card if you had one and add a 16Meg DIM ( VERY VERY EXPENSIVE ) They can be bought from IBM PC Direct . 1-800-IBM-2-YOU. Sorry about the lack of response last time but I am in the middle of drop dead deliverables for a new client. MArtin P. smith msmith@netcom.com