IBM PC compatibles, MSX, and ZX Spectrum. The latest GEOS desktop suite for IBM PC compatibles is Breadbox Ensemble. It was bundled with MS-DOS operating systems on IBM PC compatibles by Microsoft. Ensoniq's sound cards were popular and shipped with many IBM PC compatibles. The IBM PC compatibles port was developed by Quicksilver Software. MB was reserved for hardware addressing in IBM PC compatibles. The Intel 8253 PIT was the original timing device used on IBM PC compatibles. Versions were also released for the IBM PC and compatibles and the Apple IIGS. AppleTalk implementations were also released for the IBM PC and compatibles, and the Apple IIGS. BUNCH followed IBM into the microcomputer market with their own PC compatibles. Channel 0 is used for DRAM refresh on IBM PC compatibles. They implemented standard ROM BIOS routines to achieve hardware independence as had 8080 (Z80) compatibles. The game was later ported to the Commodore 64 and IBM PC compatibles. PC compatibles (CGA) and the French Thomson MO5 8-bit computer. Harvard Graphics was a graphics and presentation program for IBM PC compatibles.