disagree all you want ... you will never make a good teacher or instructor
Whoa, dude. Not trying to fight, just illustrate that it's a bit more complex than pros or even amateur builders like to acknowledge. Lots of casual people can build machines, but not too many build them particularly well. I realize the battle cry is usually, "Fu[k Dell and HP and all the others; build your own!" And it's easy for us to do that--some of us can probably build systems literally blindfolded (I prefer to wear glasses). As for me not being a particularly talented instructor, we don't know each other so let's just look past that.
Actually parts are parts. No difference at all from 15 yrs ago. Basically identical layout...you have a socket, memory slots and card slots on the motherboard. You have a PS, a cpu fan and hard drives etc to connect. Anyone who built a box in 1992 could easily do it today.
But he didn't build a box in 1992 (which as any of us who did can recall, was not exactly the best time to be a system builder...). Even so, there were 12V+ 4-pin connectors 15 years ago? There were 6-pin PCI-E molex outputs 15 years ago? How about those newfangled ATX 2.2 motherboard connections, as opposed to what passed for current even three years ago? RAM voltages don't matter right? Can I use an ATX 2.01 PSU on a new motherboard--the connectors look pretty similar, right? Should he install 20-pin or 24-pin power (they both fit the same)? Or how to configure SATA versus PATA in a BIOS? And it doesn't matter how you insert memory sticks in a multi-slot, dual-channel system, which was not an issue 15 years ago? Why do I have to hit F6 upon installation of Windows?
The number of DIY mistakes tech folks run across encompass all these issues; I stopped counting how many times people called me because their hard drives were jumped incorrectly or their CPU power lead wasn't plugged in or new video cards failed right after boot...because they didn't know their card needed a 6-pin molex connector, or worse, that it needed two, and that their old PSU couldn't handle it.
Not only are parts not parts, but physical assembly is only half the battle. I'm not saying the guy can't do it. But you wouldn't hand someone a wrench and an exploded diagram of a ten-year old engine and say, "OK, dude, go to town on this new model. It's not that much different than the old one..."
Then again, BBSes like this one are useful for fixing such things on frequent occasion.