Swapping the optical-drive assembly in a PS one is mechanically straightforward, but this replacement came with some extra problems.

In the original video I said the same method applied to all PlayStation models and that the main difference was the flex-cable length. That was too broad.

Sony used several KSM-440 optical-drive variants across the original PlayStation family. The PS one uses the KSM-440BAM, while earlier consoles use other mechanisms with different cable routing and mechanical fit. They are not universal drop-in replacements.

I also suspected some of the replacement assemblies I had bought were aftermarket units, and several in my batch showed corrosion or spindle-hub problems. That is a firsthand observation about the parts I received, not a claim about every replacement drive.

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