Mac OS X10.0: Computer With SCSI Chain Does Not Start up or Stops Responding

A computer running Mac OS X may not start up or may stop responding if the SCSI chain is improperly terminated.
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The computer does not start up, or stops responding. The mouse pointer may appear as a spinning disc, and the computer may appear unresponsive.


This is the result of an improperly terminated SCSI chain. Verify that all SCSI chains are terminated at both ends. This includes terminating any SCSI card that is the last device in the chain.

Note: A SCSI chain that worked with Mac OS 9 may not work with Mac OS X. Mac OS 9 is more tolerant of improper termination than Mac OS X. A properly terminated SCSI chain should perform better, regardless of the version of the Mac OS.
Published Date: Feb 17, 2012