PS/2 vs. USB stability for an old ProLiant DL370 rack setup?

[degov44483]

Hey everyone,
I’ve been lurking around here for a while, mostly admiring the beautiful vintage builds and deep-dives into switch physics, but I’ve finally hit a snag with my own setup that I figured only this crowd could help me solve.
Lately, I’ve been spending way too much time in my basement refurbishing some older enterprise gear for a home lab project. Specifically, I’m working with an old HP ProLiant DL370 https://serverorbit.com/pc-and-servers/ ... 53ghz-xeon. It’s a bit of a beast from a previous era, still running a pair of Hexa Core 2.53GHz Xeon processors. While those 2.53GHz chips aren't exactly going to win any modern speed records, they are surprisingly capable for the virtualization stuff I'm throwing at them.
My problem, however, isn't the processing power—it’s the interface. I’m trying to find the "perfect" mechanical keyboard to live on the rack console. I’ve been trying to use a modern mechanical board with a USB-to-PS/2 adapter to plug into my old Avocent KVM switch, but I’m getting constant dropped inputs and "ghost" key presses. It’s incredibly frustrating when you’re trying to navigate a BIOS or a terminal and the "Enter" key decide to repeat itself twenty times.
I’ve always had a soft spot for the industrial aesthetic of server rooms. There is something about the "thock" of a heavy tactile switch that just feels right when it's competing with the roar of 10k RPM server fans. My personal insight is that modern "gaming" keyboards just feel out of place next to a rugged ProLiant; they’re too light and the polling rates seem to confuse the older hardware handshakes. I’m looking for something that has that old-school, built-like-a-tank reliability but doesn't require me to hunt down a pristine Model M (unless that really is my only stable option).
I’ve noticed that some of the older KVMs are really picky about the power draw of the keyboard's controller, especially since this DL370 setup is a bit older. I’m wondering if I should be looking for a native PS/2 board from the same era as the server, or if there’s a specific modern controller/PCB that you guys have found to be rock-solid with legacy enterprise hardware.
Has anyone else here dealt with the headache of marrying modern mechanical switches to older server-grade KVMs, or is it generally better to just stick with the original "mushy" rack-mount drawers for the sake of stability?