My desktop from 2011 came with 2 PS/2(one for keyboard, one for mouse)
Yeah that was one problem with PS/2 they are distinct portsā¦ glad they are gone nowā¦ usb has been so much better.
PS/2 combo port mobos I have:
Gigabyte Z370 Aorus Gaming 5
Gigabyte X370 Gaming
Gigabyte B450 Aorus M
Gigabyte Z390M Gaming
MSI H310M PRO-VH
ASRock Z370 Extreme4
ASRock H410M-HDV/M.2
Gigabyte Z590 Aorus Elite AX is the first one Iāve had in years that hasnāt had one.
Most of the mainstream motherboards Iāve seen have had the combo port.
Popular boards that still have them:
MSI B450/550 Tomahawk
MSI X470/570 Godlike
ASUS B450 TUF/X570 TUF
Most still do, not the other way around.
Whyā¦ just WHY??? PS/2 has been around since 1987ā¦ USB was started in 1996 and it quickly became a standard in 2000ā¦ PS/2 should be long gone.
No idea but they exist nonetheless
PS/2 is still arguably a superior interface for time-critical input. It doesnāt poll as rapidly as USB can be coaxed into doing (100Hz vs 125Hz standard, 1KHz forced), nor is it even close to the same bandwidth (~12kbps vs 20Gbps), but itās interrupt based. In other words, every 100th of a second - if thereās any change in data - the system will get feedback from the port, instead of having to manually poll and ask which can be delayed by device sharing or OS-level shenanigans.
Granted I canāt think of a situation where such precision is vital. But that doesnāt mean they donāt exist. Something with robotics and either medicine or unstable/nuclear material, no doubt.
Thereās possibly specialised keyboards and/or pointer devices - or input devices which arenāt either of those - which are still in use, too, which still require a physical PS/2 port instead of a USB adaptor. After all, IBM had Microsoft keep Windows 3.0 alive until some time in the last decade to maintain compatibility between hardware still in use and the only software available to run it, and I donāt mean old 286 processors (think industrial machines - the kind most companies donāt want to spend potentially millions per unit to replace).
I would think those would have specialized equipment - not mainstream desktop motherboards - but I get what youāre saying.
Also it used to be that most USB keyboards didnāt support NKRO (N-key rollover) or even much above 2KRO, meaning that if you pressed more than a couple keys at the same time some keypresses would just be lost which can be problematic for both competitive gaming and high speed typing.
PS/2 keyboards support N-key rollover due to their interrupt-based nature, meaning that on good PS/2 keyboards you could theoretically press all keys at once and the computer would register it properly.
This is less of a problem now though ā most USB mechanical keyboards support at least 6KRO, which is good enough for 99% of users.
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My B450 board has one ps2 port. I happen to have an ancient Packard-Bell mechanical key board with a ps2 connection.
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Anything less than six is a design choice, which existed a lot in PS/2 and even XT-style keyboards. For touch typing only 2-key is considered mandatory, so pretty much all manufacturers (after the rise of membrane-based keyboards) would only build to that standard (or slightly above) due to the considerable cost reductions.
Oddly enough, most USB keyboards which do have a 6-key rollover donāt actually have to. Itās got to do with legacy settings used in communications. Enabling full N-key means it requires a fully compatible system, which wasnāt always the case in pre-EFI systems - thus most manufacturers stuck by 6-key. Not that I can really think of many situations where six simply isnāt enough, even for gaming purposes.