Curiousity Question

With Intel locking down skylake xeons to server chipsets, I looked at boards for my own amusement and noticed something. All of the boards, regardless of make, have dedicated ps/2 KB/M ports for each. Why don't they do like others and have a combo port with 2 more usb ports underneath? Semi serious question here too. Who the hell still uses ps/2 today???

PS2 is good for troubleshooting, as it is a direct interrupt to the CPU from memory
I still use a PS2 keyboard.

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Plenty of people still have PS/2 keyboards, not so much mice, aside from that one legacy mouse people keep around that you might need for working on really old hardware


Makes sense when you put it that way. I still the they should've done a combo port to allow more usb ports on the boards but that's my two cents anyway

It probably makes it easier when connecting a KVM, as most of them have a PS/2 mouse and keyboard plug and a vga connector. It would be common to use something like that with a bunch of headless servers.

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PS/2 allows for Full Nkey rollover (as many keys as you can push, all get registered.) also, with USB, keyboard polling actually takes away time from the CPU. The higher the poling, the more CPU time is taken. And because of the built-in debounce rate on decent keyboards, any polling rate above 200Hz is simply a waste of CPU time IMHO. Unlike USB keyboards, PS/2 does not do poling, instead, the switches send a hardware interrupt.
Put simply, USB makes the PC ASK, constantly, if a key has been pressed and PS/2 Tells the CPU when a key has been pressed.