Can I build a laptop from scratch?

"No, not really.

I have heard of companies like ASUS selling barebones laptops, but they are still mostly complete packages, lacking only the things that are normally upgradeable on consumer laptops, such as memory, wireless cards and drives.

The reason for this would probably be evident if you tried to take apart most laptops. They are very complicated and interweaved machines."

"[Disclaimer: I don't currently work in the mobile space.] There has been attempts in the industry to standardize laptop computer form factors. There has been some success in standardizing I/O interfaces and I understand there is a standard power plug gaining traction (I wasn't able to find a link). The mechanical design is still a major differentiator between brand models, so I don't forsee a common mobile form factor gaining as much traction as ATX has. For example, where in ATX you have space to have a standard heatsink for the processor, the laptop has a custom heatsink which dissipates heat from the whole system. It is uniquely designed based upon the system's design and component selection.

My experience from looking at laptop motherboard designs years ago is that each one is unique and when there is commonality, it is kept within the ODM/OEM."