We first got this keyboard, model number 5129, P/N 5183-7399 and S/N B01414445 REV: 1.8, as part of an HP desktop computer set back when I was in high school.
It's a good solid keyboard. Full size keyboard with 104 keys, and lights for each lock. Top bulges up and has some bonus-function keys, which are apparently still compatible with modern computers -- at least some of them are. Internet, Search, Help, Standby, Volume - and +, Mute. PS/2 plug.
I used it for a few years then, then I went off to college. Then I think for a little while it was used with a laptop whose keyboard was broken. Later, in recent years, I dusted it back off and started using it again, as a desktop keyboard for a pseudo-desktop setup with a stay-at-home laptop.
It's seen quite heavy use, pretty much daily. I've taken it apart and cleaned it at least once, probably twice I think. The plastic has started to wear off some keys -- K, L, N, M, and down arrow are entirely unmarked now, while V is getting there, and A, S, D, F, C, E, I, O, left, and right are all showing signs of going that way. (Apparently my right hand is sweatier than my left?)
But the keys themselves still work fine. The spacebar is a little finicky -- depressing it enough to make it mechanically feel it's depressed doesn't quite send the signal, and you need a teeny bit more pressure to make it register. And then it requires a slightly cleaner finger lift to make it come back up mechanically -- with a little weight it stays "depressed" but not sending a signal. But aside from this the keys work fine as far as electronic signaling goes, IIRC.
While using this computer I liked to brag at people who talked about how they needed expensive setups for gaming or needed gamepads for platformers, that I played everything with this keyboard. Because I really did.
We're getting rid of it because we're moving to a smaller space.
Nowadays I'm using a Gateway keyboard. Also PS/2, but this one's black, and is more rectangular because it doesn't have the extra buttons. This one I got in a junk pile at an office. Model number KB-2961. The keys are a little quieter than the HP 5129 keyboard's keys.
A few years ago (around 2012?), I actually bought a 107-key USB keyboard, bought new, Gear Head brand, model KB2500U, from a TigerDirect store in Pembroke Pines, Florida, for $5. (Said store went out of business since then...) I wonder if I should switch this Gateway out for the Gear Head keyboard. But as long as I'm still using the Gateway keyboard I get to brag that I'm using a PS/2 keyboard. :P