OK, this one is hard to answer. If you're asking about first "computing device" I'd say Commodore 64, actualy it was some earlier sub-version, like "64 +4" but I forgot exactly.
First x86 PC I've regulary used was in my fathers company, it was DOS based, monochrome monitor, and I?m not sure if it was 286 or 386. I wasn't that much into hardware at a time 😀
Later on they've went to IBM brand-name 486 PCs networked with coaxial cables, and "huge" 14" color displays.
From there on I've been on Cyrix, AMD K(something), pretty much all Intel CPUs except P4 as I was on Athlons back than etc etc. Currently I'm on C2D, as I'm not going after quads just yet, too expensive for what I trully need.
OK, now let's get back to "first". What have I done on first PCs.. pretty much Tetris at first, few copy/move operations from/to floppy disks and so on. Later on I remember playing Prince, than Win 3.11 and early Corel.. After 486 IBMs I got me a nice Win95 box, and that's where I can count being a true computer user, using most things I use today as well (just not in as sofisticated ways 😉 ).
I'm still thinking about those first PCs, and simply can't get my mind set on the CPU.. Except monochrome display all I remember are those huge 5.25" floppy "sheets", and that's it 😀
Fun times, but I like todays hardware and software much more 😉 though using UNIX terminals on college was fun, even though at the same time XP was already slowly looming over horizon 😉
Cheers!