How compatible were "MS-DOS Compatible" machines?

Chris M wrote: Was there ever a *vanilla* MS-DOS? I've owned an AT&T PC 6300, an Epson 8088 clone, and various Tandy 1000s, and they all came with a customized MS-DOS for their platform. The Epson MS-DOS was probably as generic as possible; the Tandy one had one or two things modified for the keyboard and something else I don't remember; the AT&T one had extra handling of 720K 5.25" disks (the drives were capable of 80 tracks if you set a DIP switch) and the date/time command knew how to talk to the AT&T's clock chip. My friend had a Sperry clone. That had a special MS-DOS that my 6300 could boot, but his Sperry could not boot my 6300's DOS. IIRC, MS-DOS versions 5 and later were mostly sold retail as Microsoft had mostly gotten out of the specialized MS-DOS business (due to lack of demand) by 1990. -- Jim Leonard (trixter at oldskool.org) http://www.oldskool.org/ Help our electronic games project: http://www.mobygames.com/ Or check out some trippy MindCandy at http://www.mindcandydvd.com/ A child borne of the home computer wars: http://trixter.wordpress.com/