As for OS9: I installed it on a used Power Mac 9500/132 with 128Mgs of RAM. The replacement hard drives (non-Apple) were partitioned into four volumes and only one would accept OS9. I can't say that I've had any problems, but as a designer my files have not yet exceeded 1.2Mgs. The only problem I do have is with the speed of Appleworks 6(!).
So don't be discouraged. OS 9 was really intended for the G3's and G4's, not the older machine I have.
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