Intel® USB 3.0 eXtensible Host Controller Driver — Why did Intel release two Windows* 7 USB 3.0 xHCI

Why did Intel release two Windows* 7 USB 3.0 xHCI drivers? ... Why did Intel release two Windows* 7 USB 3.0 eXtensible Host Controller (xHCI) drivers? There are two different Intel® chipset platforms for Windows 7, each platform has its own USB 3.0 xHCI d

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