Convert Half Duplex to Full Duplex

[CRL]

Compaq FAQ: Internet Phones for Presario Notebooks (FAQ3052)
The Compaq Presario Notebooks have not been tested for use with internet phone software. Internet phone software may require a full duplex sound card to work properly. Your system has a half duplex sound card. Compaq does not support a sound card upgrade.

Question: Does anyone know if a driver is available from another source?

CRL

[glc]

You cant convert a half duplex card to full duplex with a driver. You will have to find an internet phone that works half duplex.

[reboot]

Drivers cannot change hardware.
If you have a half duplex sound card, that's all you've got. Unless you wish to disable the sound card (not even sure if you can in that laptop), and purchase an external kit with a duplex card, you're SOL.