Is the Zoom X5 ADSL Modem compatible with SBC Yahoo DSL?
Yes, it works using the default settings for PPPoE LLC (VPI=0 and VCI=35). These settings are also documented in Appendix A of the manual (page 43) as 1 of 3 possible SBC settings. Just need to enter your username and password on the Basic Setup web page to get up and running. This modem however is not supported by SBC.