You need to install these prior to logging onto the Windows Update Server. Once you log onto the Windows Update Server the very first Download prevents these Drivers being successfully installed well at least installed and working.
Here you need to install the OS XP in this case load the Sound Driver, then any other drivers that need loading then load a AV Product, update it as required and then finally you can now log onto the Windows Update Server and accept the 2 Downloads to start the update process.
You'll have to do a Repair Install of XP so follow the directions under Method 2 at this
Web Site.
http://support.microsoft.com/kb/315341
You'll need a M$ Branded Install Disc to do this not a System Makers Recovery Set or a Slipstreamed Install Disc. You'll also need to reapply any Service Packs and Hot Fixes after you finish. ;)
If you have not logged onto the Windows Upstate Servers open the Control Panel, switch to Classic View and open the Sound & Audio Devices, under the Audio Tab make sure that the Realtech Device is listed in Playback. If it's not the default Sound Device use the drop down arrow and change it to Realtech. Do the same with the remainder of the settings in that Windows and save the changes.
Col