> Once we got to the point of the Intel Core Duo (06-08) the modern processor was fast enough for the majority of the PC fleet
Core 2 era was definitely the change-over point for me - before that I was upgrading pretty much on a yearly basis. I then built a Core 2 Quad machine in mid-2008, and stayed with the same hardware until mid-2013. TBH, that upgrade (to a i7-4770K) wasn't really necessary - I only did it because I started doing a fair amount of HD video encoding/editing. The Q6600 was handling everything else fine.
After the Core Duo we got integrated graphics, built-in video (etc) support, and lower TDPs that allowed thinner laptops with longer battery life. Oh, and lower prices.
We also got 10-second start-up times via UEFI.
There are more things to PC life than raw single-core performance ;-)
Core 2 era was definitely the change-over point for me - before that I was upgrading pretty much on a yearly basis. I then built a Core 2 Quad machine in mid-2008, and stayed with the same hardware until mid-2013. TBH, that upgrade (to a i7-4770K) wasn't really necessary - I only did it because I started doing a fair amount of HD video encoding/editing. The Q6600 was handling everything else fine.