So there is a similar version, but the HD version is more efficient VIA C7-M 784@1.8Ghz + Via chorme9 HD is more efficient than q6600@2.4Ghz + Via Chrome9 HC. That's the difference. For details please do not ask me, this is just another version. http://www.viaembedded.com/en/products/processors/productDetail.jsp?productLine=5&id=1392&tabs=1