If you want a laptop to tear into and learn from, the old samsung x86 chromebook is hard to beat. ram and disk are standard and upgradable, you can put a clip on the flash part, ... it's just a very hackable machine. I still have one and really like it.
More recent ones to mess around with include the acer c720.
The difficulty of dealing with chipsets is what keeps me pushing on chromebooks. It's a real time saver. I'd still like to find an AMD solution however.
ron