I just assembled a 3930K/X79 Extreme6/GB system on a tech bench. I'm in the process of verifying the functionality of all the ports/connectors. Everything seems to work except for the USB 2.0 connectors at the bottom of the motherboard, USB_4_5, USB_6_7, USB_8_9. The USB 2.0 rear connectors work. I've tried to different USB brackets.

Are the front panel USB ports running off the same controller as the rear?

Is there something else I should check before I RMA the board?