Bad idea: 16bit bitslice x86.
Your motherboard has 4 sockets. Fill one, and you can only do 16bit, so DOS (but no doom) and windows 3.x (but no enhanced mode).
Fill two, and you enter the wild world of 32bit! Finally you can use windows 95 and up.
Fill four, and now you can access more than 4gb, allowing you to load one (1) web page!