Xanto: And your right in the fact you can keep an old machine around... but old machines break, and when something is old it becomes much harder to replace non working parts. Like today, try finding parts for an old 95 computer. It's possible but gets harder with each passing year. You don't have as much control over these things as you may think. Sooner or latter your old machine will get left behind.
Have you actually done/tried this? I'm asking because as I said, I actively maintained computers with decade-old hardware, I did that for a long time, and I _never_ had a problem to get parts that I needed. In fact, I find that parts are usually so easy to come by (and at no cost at all, if you just look at the right places) that I got piles of much more parts than I can possibly use. I have about a dozen mainboards and CPUs, two dozen graphics cards, and countless RAM sticks of all imaginable standards lying around here, and I didn't even pay a single cent for them. And I didn't even spend _time_ collecting them, most of that stuff was picked up for free while looking for something else.
More than 400,000 _tons_ of computer parts are discarded every single year in the US alone. This figure does not include monitors (that's another 600,000 tons). Numbers in Europe are probably in the same league, perhaps a bit lower. Given these massive amounts, if you really have difficulties finding older parts then I can only assume that you're not looking very hard.
So, please tell me, which parts exactly did you look for, and where exactly did you look for them?