On the Intel Sandy Bridge motherboards in stock that have USB 3.0 (DH61BE/DH67BL/DH67BL/DP67BA/DQ67SW), the ports will work if you have a USB keyboard/mouse hooked to them and you are setting up the motherboard BIOS.
If you have a USB keyboard/mouse plugged into the USB 3.0 ports on these boards during operating system installation, the keyboard/mouse will not function. This is due to the USB 3.0 functionality being provided by a separate chip on the motherboard vs. being natively supported by the chipset. The Windows 7 kernel does not have native support for this chip.
Once the OS is loaded and the USB 3.0 driver is loaded the ports will function normally.
It is recommended that during OS installation that you use the USB 2.0 ports for keyboard/mouse.
|The USB 3.0 Ports are Blue|
Tip Courtesy of Greg Mann.