aries-mu wrote on 2023-09-26, 13:50:
Anyways, I never thought about the PS/2 ports issues. I always took it per granted that I would have found them on any mobo, at least back to 386s.
This mouse problem thing, I hadn't considered at all!
My face when I got this 486 DX fresh a few days ago, I look at it and I'm like: Where the heck am I gonna plug the mouse???
Yea exactly.
Back in those days there were basically two types of machines:
1) Brand machines, which usually had their own custom formfactor, for which they developed their own motherboards, which usually integrated quite a bit of functionality on-board, to cut costs and keep the machines relatively compact.
2) Generic clones, which were built from off-the-shelf parts, where the motherboard was generally just CPU+chipset+memory, and nothing else, using the standard AT form factor. So you'd need a multi-IO card, that generally offered a floppy controller, IDE controller, a printer port and two serial ports (IBM's PC, XT and AT machines were designed the same way, using expansion cards for basic functionality, but PS/2 was more integrated).
Some brand machines also integrated the video, but quite a few used a standard video card in an expansion slot.
It wasn't until the late 486/early Pentium era that integrated chipsets became more standardized for generic clones, with both Intel starting to offer highly integrated chipsets, and also various cheap Taiwanese clones became available (Ali, UMC, VIA, SiS etc).
This meant that the multi-IO was now often integrated on board, so you only needed a video card to get a working machine.