When I was a lad, one of the big selling features when you bought a new PC was the ability to upgrade it. Add memory, plug in a second-hand drive and, if the budget allowed, swap out the processor. But over recent years, Apple has taken that ability away. Even RAM upgrades, which used to be easy, were made impossible as Apple's quest to make everything as thin as possible drove them to soldering everything in place. But iFixit has revealed in their teardown of the new 21.5-inch iMac that the memory and processor can both be upgraded.
The ability to add more memory is a no brainer for me. My usual buying behaviour used to be to purchase a computer with the least amount of memory I needed at the time and then upgrade a year or so later as a treat to myself. I'd do the same with hard drives although most recently that's been about replacing hard drives with SSDs to give systems a performance boost.
iFixit says the new 21.5-inch iMac has a modular CPU so, in theory, you could swap it out for a faster unit when prices come down in future. Of course, you'll be running the gauntlet of a "Warranty Void if Removed" sticker.
I've swapped out plenty of drives and added lots of memory but I've never bothered with the processor. So, would you do it? When was the last time you replaced a CPU in a PC? Have you ever done it?