Você precisa descobrir qual o número do modelo do seu componente de áudio.
Como o driver do Vista (e, espero, o 7) que encontrei neste link , funciona apenas para alguns modelos:
The Sigmatel AC97 audio driver is for Windows Vista, Windows XP or Windows 2000. Technically, it is the rather long winded: Sigmatel C-Major STAC 9750 AC97 WDM Audio Driver. Whatever way you want to label it, the driver package installs version 5.1 of the driver onto your system and can be used as an update to an earlier driver or as part of a new installation. The driver can be used for the following Sigmatel models: STAC 9200, STAC 9204, STAC 9205, STAC 9220, STAC 9221, STAC 9223, STAC 9227, STAC 9228, STAC 9229, STAC 9230, STAC 9254, STAC 9255, STAC 9271, STAC 9272, STAC 9273, STAC 9274.