What version of Windows are you using? I assume you connect to the DSL Modem via an Ethernet cable using the builtin LAN connection and you are looking for the driver for it?
Integrated 3Com 56 Kbps3 Modem + LAN (Ethernet 10/100) via Mini PCI type IIIA card with wake-on-LAN, PXE and WfM 2.0 compatibility (standard higher-end models). Modem-only and no-modem models also available.
XP driver:
http://h20000.www2.hp.com/bizsupport/TechSupport/SoftwareDescription.jsp?locale=en_US〈=English&pnameOID=27093&prodSeriesId=31763&prodTypeId=321957&basePartNum=ob721&locBasepartNum=ob721en&os=Microsoft+Windows+XP&tech=Driver
98
http://h20000.www2.hp.com/bizsupport/TechSupport/SoftwareDescription.jsp?locale=en_US〈=English&pnameOID=27093&prodSeriesId=31763&prodTypeId=321957&basePartNum=ob676&locBasepartNum=ob676en&os=Microsoft+Windows+98&tech=Driver
Ron