I'm not a computer hardware guy, but even I figured out how to add more RAM and a new hard disk to my old Macbook Pro.
That said, I added it last year to my late-2008 Macbook Pro so that I could keep using it for simple stuff at home like browsing HN and watching YouTube.
At work, my professional machines get replaced every few years, so I've never had to monkey with the insides. They're capital assets, and once the depreciation is fully taken, there's no point in holding onto them. We sell them and get new ones.
So the question is, what does it mean to be a "professional" developer?