OS 7.6.1 can run elegantly on a 68030 PB160/180 (25 and 33MHz) with 14MB (max.) of RAM, so a PB5x0 with an LC040 and 20-36MB can do at least as well. However, OS 8.1 is their limit. There is a wide choice of system software to use with a 5x0, not the least of which is System 7.1 upgraded to '7.1.3' and retrofitted with elements from 7.5. The System Enablers come en bloc with System 7.1 Update 3.0, or from Apple. There are also the 603e (100 and 117MHz) daughter cards which, although uncommon, turn up from time to time. LC040 daughter cards are common and cheap if you come to need one.
The Rev. A and B PCMCIA card modules are for the 68k 5x0s, as opposed to the henstooth-class Rev. C module that is obligatory for use with a PPC processor. A second battery is more useful most of the time than a PCMCIA module. An AAUI/RJ-45 adapter is a perfectly useful alternative to a PC-card for ethernet, and much more easily implemented.
You are more likely to have difficulties with the 'smart' (Hah!) NiMH batteries of the 5x0s than with their logic components, and working AC adapters are also getting scarcer as time passes.
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The Rev. A and B PCMCIA card modules are for the 68k 5x0s, as opposed to the henstooth-class Rev. C module that is obligatory for use with a PPC processor. A second battery is more useful most of the time than a PCMCIA module. An AAUI/RJ-45 adapter is a perfectly useful alternative to a PC-card for ethernet, and much more easily implemented.
You are more likely to have difficulties with the 'smart' (Hah!) NiMH batteries of the 5x0s than with their logic components, and working AC adapters are also getting scarcer as time passes.
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