FF
Have you reloaded the AOpen motherboard drivers since rebuilding? The Alacatel DSL modem (USB) is looking for USB2.0 support, which the AOpen drivers will give you...
Suggest you start in safe mode and remove the DSL modem
Then start normally and install the MX6B motherboard drivers (usually on the CD that came with the PC or available from the AOpen website - "VIA 4-in-1" they are called [or something similar])
Reboot and reinstall the DSL modem -- is this the BTOpenworld modem with BT software?
HTH