> When your processor is too slow, buy a new CPU, or you get a new heat sink and over clock it
The motherboards for PCs built 5 years ago are completely different from those built today, and the CPU sockets have changed every other year. New processors from Intel will be soldered on.
The performance of a PC from five years ago is probably adequate for web browsing and office tasks. For anything more demanding, the advances in power consumption, execution efficiency and process node are huge leaps from five years ago.