I replaced the motherboard on my note 9 and the numbers didn't match but it worked make sure they are the same shape and that it has the right connectors before you buy if you are unsure ask the seller if it can replace your board they'll tell you if it's good for your device or
Greens definitely dead pixels black may be the same my monitor sports a red dead pixel I believe it's the manufacturers intended way to scare people into buying a new
Windows 10 today is not compatible with 4gb of ram back when it first came out it happily took 2gb you could replace windows xp with a fresh install of Windows 10 but now so much has been added it will only run reliably on a minimum of 8gb recommended 16gb so upgrade your ram to start with then work from