Before installing HD audio codec driver please make sure Win XP has been updated with Service Pack. If Service Pack has not yet been installed, please try install service pack through Windows Update.
Please make sure service pack and patches are properly installed. If SP1 or SP2 has already been installed, kindly make sure that the system is not overclocked and also that onboard HD audio codec works at default settings. Follow by inserting the driver CD's which is provided with the motherboard, when prompted with a pop-up box please select "Xpress Install" on the top right corner to install all the necessary drivers.
If you want to manually install the HD audio drivers then you will have to firstly download the Microsoft UAA Bus driver and install it. After you restart the system please check the model of your onboard HD audio codec, and download the matching audio drivers for installation. After the mentioned procedures are done the onboard audio should work accordingly.
If SP3 has already been installed, kindly download ths latest HD audio drivers from GIGABYTE's or audio chip vender's website to install directly. PS: When installing older HD audio drivers on Win XP with SP3, system may appear a message which is about Microsoft UAA Bus driver isn't been installed yet. Please use the ths latest HD audio drivers to install.