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IBM 5170  -  Failures of the CMI 6426 Hard Drive


The first hard drive supplied by IBM in the IBM 5170 was CMI's model 6426-S (sometimes referred to as the CM-6426 or CM6426).
The very high failure rate of those drives led to IBM moving to the Seagate ST-4026.

Below are some magazine articles relating to the failures.

The specifications of the drive are shown on page 2 of the CMI document here.

Date:	January 1985
Magazine:	Computerworld Magazine of Jan 21, 1985
Article:	Microsoft: PC-DOS release will solve start-up bugs in AT drive
Comment:	DOS 3.1 released.  Better copes with bad tracks at start of drive.  See here for the limitation (not a bug) in 3.0
Date:	March 1985
Magazine:	InfoWorld Magazine of Mar 11, 1985
Article:	PC AT Problems Cause Concern for Owners
Comment:
Date:	June 1985
Magazine:	PC Magazine of June 25, 1985
Article:	The AT's Slipped Disk
Comment:
Date:	July 1985
Magazine:	InfoWorld Magazine of Jul 22, 1985
Article:	Reliability is Hard Disk Key
Comment:	The 6426 is one of the drives compared and negatively commented on.
Date:	October 1985
Magazine:	InfoWorld Magazine of Oct 7, 1985
Article:	AT Gets 30-Megabyte Hard Drive
Comment:	Release of the IBM AT model 239, a model that has a 30 MB drive made by IBM.
Date:	April 1986
Magazine:	PC Magazine of April 29, 1986
Article:	From Sea to Shining Sea
Comment:	This is an excellent summary.
Date:	2016
Article:	Core's publicity stunt of 1985/1986