For anyone else searching after all this time like I was for the oddity that the M50 front usb board connector is. The answer goes along with the previous one.
Yes it's the standard usb 4 pin dual row pinout. When looking at the mother board port and the IBM screen print right side up
2 4 6 8
1 3 5 7 9
Port 2 Vcc U- U+ G
Port 1 Vcc U- U+ G G
Pin nine is indeed ground! BUT in order to sense this extra front port hub in bios, you MUST tie all ground together. I just short jumpered my stock case usb 2 port header so pins 7 8 and 9 were tied together.
The native OEM front port panel connector jumpers these in the black main shell....