This is a terrible idea. Microsoft going into the hardware business will drive out all the OEMs. And soon, the only one making Microsoft hardware will be Microsoft.
I hope MS learns from Apple. If you want an iOS device, you have to buy it from Apple. A monopoly can only drive up the price. Consumers lose.
If Apple allowed OSX to be installed on non-Apple hardware, you'd have dozens of OEMs producing OSX-based machines to compete against Apple. As long as Microsoft allows you to sell hardware with Windows installed on it by merely paying a licensing fee, you're going to have hardware companies selling Windows-based hardware regardless of what Microsoft does.