AST RESEARCH TECHNICAL BULLETIN TB-0277 05/27/87 IBM XT-286/DESQVIEW 1.11 The IBM PC-XT 286 does not allow for quick removal or disabling of the motherboard's 640K memory. Therefore, it is not possible to create EEMS (backfill) memory with the AST Rampage 286. At this point, DESQview would not be able to bank switch memory from the 640K area which would mean that multi- tasking operations could not take place.