Think of it like a buddy system for tablets. Each chip company--Intel, Nvidia, AMD, Qualcomm, and Texas Instruments among them--would pair off with one vendor, such as Dell or Asus, and work only with that hardware partner on the next generation of Windows tablets.

Bloomberg, which based on three unnamed sources, says this rumored directive from Microsoft isn't mandatory, but partnering companies will receive incentives, such as lower software prices or features that make the software run more smoothly. The standard version of Windows that runs on laptops and desktop PCs won't have these restrictions and incentives, the sources say.

This appears to be all about control. Pairing chip makers with computer makers would limit the number and variety of Windows tablets hitting the market, which may in turn accelerate development and testing.

Microsoft's rivals, Apple and Google, control hardware in different ways. Google lets chip makers and hardware makers partner at will, but has of its Honeycomb tablet OS and reportedly requires of all software tweaks by device makers who want early access. Apple designs its own hardware as well as the processors inside, so the company needn't deal with computer makers or chip makers.

Microsoft's approach may not go over well with all computer makers. On Monday, Acer Chairman and CEO J.T. Wang said Microsoft was putting "" restrictions on processor makers. He wouldn't comment on specifics, but said Microsoft was "really controlling the whole thing, the whole process."