MODE32
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MODE32 is a software product originally developed by Connectix for certain models of the Apple Macintosh. It was published in 1991 and originally cost $169, however on September 5, 1991, the software was made available for free to customers under licensing terms with Apple Computer.
[edit] Overview
MODE32 effectively removes a ROM flaw in certain models of early 68020 and 68030 Apple Macintosh computers (see below), which were advertised by Apple to be 32-bit. Despite the machines' hardware being designed to accommodate for this, older, non 32-bit clean software in ROM forced these machines to run in 24-bit mode. The "dirty" software in ROMs crippled these otherwise high-end machines to support only 8 MB of RAM. Customer dissatisfaction likely prompted the licensing agreement with Connectix.
The software runs as a control panel in Macintosh System 7, enabling the 32-bit addressing option of the operating system. The option can be found in the memory control panel when MODE32 is enabled. Otherwise the option is not displayed.
Generally, 32-bit addressing is only needed when large amounts of RAM are needed or when a software requires it. Running non-32-bit-clean software in 32-bit mode on any Macintosh can cause crashes and data corruption (see Low End Mac link below).
[edit] Affected models
Other models do not need MODE32 because they either do not support 32-bit addressing at all or support it exclusively.
