Currently there are no drivers are available for Windows 8 for Intel D101GGC board. You have to wait for some time until D101GGC audio driver for Windows 8 is released. However you can download Windows 7 drivers and can try installing them on Windows 8. It’s not sure whether they would work fine or not. Make sure that your data is backed up before you install the drivers.
The drivers can be downloaded from Intel’s official website. Audio driver can be found by following the link below:https://downloadcenter.intel.com/SearchResult.aspx?lang=eng&ProductFamily=Desktop+Boards&ProductLine=Third-Party+Chipset+Boards&ProductProduct=Intel%C2%AE+Desktop+Board+D101GGC
Hope this helps.