I’d say things got “boring” quite a while after the pentiums. All the peripherals like the cd burner got faster. Memory got larger and faster. Video got substantially faster. Network went from 10mbits to 1gb over time. Smarter power management started to exist. USB came online. Wi-Fi started to exist.

I’d say things got “boring” after the clock wars. Now says the clock is basically the same as it was 5 or even 10 years ago (though massively more parallel, etc). Average memory size seems to have peaked around 16gb (though substantially faster and more parallel). Average disk size has remained about the same (though way, way, way faster thanks to SSD’s).

Also things have gotten much smaller and more energy efficient. Back in the day your motherboard had all kinds of discrete shit on it. The board was huge in comparison to a modern board.

Note: it’s been a good 10 or 15 years since I’ve built a desktop PC from parts… I kinda miss it.