It's way easier to get rid of an entire computer second hand than it is bespoke parts that you've replaced, so this is what I do too. I used to be on a 4-year cadence with new PCs, but then I kept getting more and more mileage out of my machines, since graphics don't leap forward so quickly like they used to. My current machine is 5 years old and still runs the latest games on high settings.

Heeeey, it's me! Your sibling! You got any of that sweet sweet ddr5 ram??? Don't hold out on me, boy!

I got my friends old box the same way. I'm into games that don't require all that much. And will also use it to play minecraft with my kids.

Well... I did upgrade mine progressively, I don't think it still has any original parts, maybe some sata cables? I was able to get a smaller pc offspring out of this, ended up as my nephew's gaming rig, does it count as my old rig? are both the same rig? damn computer of theseus causing philosophical problems!

Domated mine to the after school "day care".
They helped me so much, I wanted to repay it in some capacity

that is the hand me down way, saves money to buy a new one. im not a heavy gamer but i do get hand me down from someone who games.