I have an old laptop that that has a broken HDD. Since I have to replace the HDD and all the other parts are old I thought I would try to replace all the parts. However I have never done anything like this before and don't really know what I am doing.
When I buy new parts do I just need the socket to match the motherboard? or are there other restrictions? Is there a way to tell if the new part will fit into my laptop's case? How do I determine what power source I will need? Do I need to worry about cooling or will the individual parts come equipped with all the cooling they will need?
Also I don't know which motherboard I have. I imagine I need to know what board I have to know what parts to buy. Is there a way to determine what motherboard I have without turning the laptop on?
Also I was wondering if it would be possible to use the parts from my laptop to boost the abilities of my even older desktop?
And finally any additional comments you have for a noob about building a laptop would be greatly appreciated.
Not worth it in any way. Most motherboards will only fit that model and only have connectors that work with that motherboard. With what replacement parts go for, and new laptops, you're better off buying a new laptop.
And, no, just about zero parts from a laptop will work in a desktop.