I would put a separate fuse on each power supply. Whatever is standard for the computer (3A?), and probably similar for the power supplies. Bear in mind the surge current when you switch it on will be quite high. In my case switching on the stepper motors briefly dims the light in my workshop.


Oops, just realised you're talking about a switch not a fuse Nevermind I'll leave this here.

I'm liking where you've chosen to mount the electrics.