This modem is found in Dell computers. It is an ISA style card and will identify on a PnP search as "U.S. Robotics x2 Winmodem Voice" - this set of files has everything you need to get the modem happy. I spent hours finding this stuff and hopefully it will do you some good!
The following files are found inside the driver download file.
|turbovbf.vx_||3.9 KB||4 Oct 1996|
|Mdminfo.ini||693 bytes||3 Jun 1998|
|Winmodem.inf||59.8 KB||15 May 1998|
|Wmldr.vx_||3.5 KB||1 Apr 1998|
|Wmexe.ex_||25.3 KB||1 Apr 1998|
|wmwave.inf||1.1 KB||1 Apr 1998|
|turbovcd.vx_||9.4 KB||4 Oct 1996|
|Wmaudio.vx_||3.4 KB||1 Apr 1998|
|Winmodem.vx_||343.0 KB||1 Apr 1998|
|Wmdll.dl_||21.8 KB||1 Apr 1998|