I can think of two possibilities:
1) The hubs are not enabled in bios
2) The header pinouts are not the same (not applicable if these are actually on the board itself)
Also beware that some serial/firewire headers look just like USB ones !
If you have the USB sockets on brackets then unles they were supplied with the board this would be the cause.
Fortunately the colours are standard so you can compare these against your motherboard manual.
One tip with testing. I always test with a passive device such as a mouse as this reduces the risk of damage if you have made a mistake.