There is a modem chip running change on Prespa. So release modem driver.

For Vista-->no need to change the driver
For XP-->Pls help to update to version 2175, since this version of driver is not compatible with the old modem
hardware

How to identify the modem: 

Pls check >Control Panel>System>Device Manager>Agere Systems HDA
Modem>Detail>Hardware ID>
1)Old modem is HDAUDIO\FUNC_02&VEN_11C1&DEV_3026
2)New modem is HDAUDIO\FUNC_02&VEN_11C1&DEV_1040
