Microsoft Rejects a Greener USB 2.0 Opportunity. Why?

On the eve of the release of Windows 7 the much heralded successor to the infamous Windows Vista, one interesting question has been raised. In August, Intel, who needs no introduction, announced a change to the USB 2.0 specification. This change accompanies similar proposals by other groups trying to stem the wanton electricity wasting by computer systems. PCIe video devices as well as Ethernet connections both are having their hardware controls extended to allow software developers the ability to lower their power consumption. Primarily this would entail trimming power needs while the device is not in active use. This seems an ideal fit for USB connected peripherals which can have a much higher 'idle' time per day than any other connection type. Why then would Microsoft snub their nose at incorporating the change?

The top functions being introduced into the specification are Link Power Management (LPM) and Per-Port Change Events. LPM provides handles for host controllers to use Suspend and Resume functions to USB devices. Per Port Change Events will reduce the impact of polling events. Currently, Microsoft's Active State Power Management lowers power sent to each individual serial connection, this update would let the devices manage their own power usage and merely report their capabilities to the host. All these will require new EHCI controllers, meaning Intel has to ship a new generation of USB 2.0 chipsets to support these energy saving features. But since the same features will come with USB 3.0 anyway, let's hope MS and Intel are just busy getting the next gen. USB working on Windows 7 at the very least.