There is a very, very good reason we don't have homebrew x86 boards. They're incredibly difficult and expensive to design, produce, and verify. Modern hardware

There is a very, very good reason we don't have homebrew x86 boards. They're incredibly difficult and expensive to design, produce, and verify. Modern hardware has crazy high clock rates and even tighter timing tolerances. Beyond that, you have to convince whichever OEM to sell you the chipset in small quantities. And then you have to write miles of drivers and firmware and a BIOS. And then you need to acquire and test every combination of CPU and RAM that any customer might conceivably use, then patch your miles of firmware to support each chip. Oh and also you have to ensure your firmware can never, ever fail in such a way that cuts off fans or cranks up CPU voltage. It's an incredibly involved process, which is why only big companies have the resources to pull it off. It's not impossible for a community board to be made, but it's something that would take years of work and a lot of money.