Same boat, my computer is basically the computer my wife built probably about 12 years ago before we got together, it was pretty beefy for its time. I basically stuck her old components in a new box (and also stuck a newer graphics card in it because I got a really good deal on a used 2060)

Still manages to run most games out there on acceptable (to me) settings.

Made the switch to Linux about a week ago, no major issues, some things are arguably running better now. It's not without its hiccups but so far things have gone pretty smoothly.

EDIT: went with Mint over Zorin though.

I've got an Intel 6900K 8-core X99 system. Also not compatible with W11, but serving me well.

The issue is even if I wanted to upgrade, that market segment is effectively dead; X299 and X399 (AMD) were the last real HEDT platforms. The only thing now is workstation tier boards, which are about $1K and processors to match

I've been using a PC with C2D till it died. And I'm still having thoughts of checking whether it's solvable with a bit of soldering, perhaps replacing power.

It's enough for music, text editing, a little bit of web browsing and old games. Old games here includes a lot of goodness, but even World of Tanks worked under Wine on it back when I used it. Slow, but playable (when you have friends and it's a social event, alone kinda sad).

My desktop (that runs guix) is from 2009. At the time I built it for gaming. In the last couple years I upgraded the ram to 16 gig and replaced the graphics card (old one died), no other mods made. Now I use it for much more mundane stuff and it's still completely usable.