IBM XT

The IBM XT was an extended version of the IBM PC. It provided extra slots, while removing the adapter for the tape drive. The IBM XT was also sold with a hard disk drive, along with a floppy drive, or as a dual floppy drive system. Since the 8088 CPU could address 1MB of ram, the memory map was split in a 640k for OS & programs, and 384k for hardware buffers and ROMs.

The IBM XT was later replaced by the IBM AT.