Building a laptop is possible, but I would strongly recommend against it.
Anyone who has stripped and rebuilt a notebook will tell you that there is little margin for error, and I have yet to find a components supplier where you can save enough on the guts of the machine to warrant building one to begin with.
There are places now where you can buy a well specified notebook for far less than you may have thought possible.
When these machines come with licensed software, a warranty (not to be sniffed at) and taking into account that they (usually) work straight out of the box I see little point in the time investment in soucing the necessary components and then building the machine up.
Laptops, in my opinion, should be bought and used as they stand, then renewed if/when required. Updating them is normally confined only to memory and hard drive alterations and, as I've already said, finding the components is not the problem - price to buy them is.
Just my tuppence worth.
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