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Replacing IDE HDD with optical drive on Performa 6320CD
Posted by: croissantking on 2026-02-15 03:12:20
erm . . . the cooling fan exhausts out the lid.
Or just space it off the surface? Nothing you couldn't fix with a book - the vents are near the rear of the case.

Thanks for taking seriously my slightly facetious comment 😛

I have several old drives lying around and tried all of them, no luck. None detected. Must be ROM level hardware limitation. Probably the machine looks for HDD, not an optical drive on that port. I'm not an expert but I think a modified ROM or device driver is needed.

I agree about hardware limitation but just for the sake of covering all the bases, can I ask which version of Mac OS are you running, and therefore which version of the Apple CD-ROM extension is enabled?

Exactly, no complaints about the switch to IDE in the Quadra 630/PB190 and up at all. The switch was even earlier. High end BlackBirds, employing an interstitial adapter for higher capacity IDE drives.

Were these early Macs using a SCSI to IDE adapter integrated on the logic board, or was it native IDE?

The switch from SCSI to IDE mass storage was one of the better moves by Apple despite LEMlike lore about the drives being cheaper and slower than SCSI drives. It wasn't, it was at least as fast and a member here or maybe on TD did benchmarking, finding it equal to or a tad faster than the Apple's SCSI implementation.

Is there a greater load on the CPU for accessing IDE drives vs SCSI?
Posted by: Phipli on 2026-02-15 03:14:40
Were these early Macs using a SCSI to IDE adapter integrated on the logic board, or was it native IDE?
630 has IDE implemented in one of the ASICs. No bridge.
Posted by: Trash80toHP_Mini on 2026-02-16 09:54:46
IDE is handled within the SCSI architecture of the Mac, but is IDE as far as the Drive is concerned.
630/190 are natively IDE, sorta kinda.
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