I was wondering when people consider themselves to have a new PC. Technically I've had the same PC for close to 20 years now, but every part's been upgraded several times over.
I figure everyone's got a different mind about it. For me, I'd have to say when all of the big three—CPU, GPU, mobo—have completed a phase, my brain thinks of the previous setup as "the old PC".
Technically my my PC is the same PC I used decades ago. It started as a Pentium 3 with... 64MB of RAM if I remember, and something like a whopping 10GB hard drive. It's still the same PC of course, I swear!