No sound after clean install of XP
Are you sure the speakers are not muted? Right-click on the speaker icon in the Taskbar and select 'open volume control' and make sure that the checkboxes are unchecked.
Open Control Panel and double-click the 'System' icon. Select the 'hardware' tab and click on the 'advanced' button. Expand the tree 'sound, video and game controllers'.
You might see a yellow coloured icon in the list suggesting that there might be a missing driver or similar.