I have found "ATI SB450" is related to realtek sound chips "ALC262, ALC268, ALC660, ALC861, ALC861VD, ALC880, ALC882, ALC883, ALC885, ALC888" - if you see such on your motherboard - try to search driver for it.
If you have trouble to find it via english sites, try
this in russian: enter numbers from picture and press link below ("Скачать")