Maybe, but it would require extensive modification and a new hard drive, since the system board connectors are different. Also, the LC 575 supports an internal SCSI hard drive, while the LC 580 uses an internal IDE hard drive.
Frankly, you’re better off finding an LC 580 if that’s what you want to end up with.
Update: Chris Lawson notes that the 575 can use 64 MB 72-pin SIMMs for a total of 68 MB of memory. It is not known if it will work with 128 MB SIMMs. Also, the 580 uses SCSI for its CD-ROM, so it should be possible to use a SCSI hard drive.
Keywords: #lc575 #lc580 #performa575 #performa580
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