Apparently, if you want to buy motherboard pin-header sockets (like for the HDD LED or power-switch connectors), you have to know in advance that they're called "dupont style" housings. Sheesh. Cause that's obvious.

Thanks a lot, hardware people.

PS - Yes I still have zero clue how to divine the names of less common pin formats, like the one I'm stuck wiring up in my Linux-car's steering-wheel adapter. So it just stays on the floor of the garage.