There appears to be a conflict between the Toshiba 540 MB hard drive and sleep. Reformatting with updated drivers that are compatible with System 7.5 does not help. The same versions of Third-Party drivers on other hard drives with System 7.5 does not result in this failure. It appears to be strictly related to this hard drive.
The workaround is to reinstall 7.1, 7.1.1, or 7.1.2 to alleviate this problem.
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