I am a complete novice on PC builds and always just went to the local MicroCenter and spoke with a very knowledgeable lady named Pat.
Last Summer, my i7-4770K cpu died. It had been about 6 years, and I figured it was time to update. Not so. I was told that the only Intel processors that will still run Win 7 (I use Win 7 Pro) are socket LGA 1150 and LGA 1151. I have not researched that fact.
There are/were some boards and new processor for the LGA 1151 socket. I ended up buying a used i7-4770K (socket LGA 1150). In fact, I stocked up on a spare i7-4770K and my old reliable MoBo. When those finally die, I will probably switch OS, maybe Linux, but that switch will be painful as my favorite CAD programs are probably stuck on Win 7.