To the original question... in theory it would be better to mount the drive horizontally instead of vertically. The thinking being that it's easier on the drive heads.... less wear on the drive heads having to move side to side, rather than up and down.
I'm an older man; and here is my thought based on 31 years in electronics: 1- It does matter vertical or horizontal; But: 2- to know exactly which way: you have to open one drive of they type you want to use for long term and study all the ElectroMECHANICAL components and effects. Just to give u a simple confusing; if horizontal is better for gravity point of view; then you should know that many pallaters have arms under the plate also; so good for one side, bad for the other, ... and so on.
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