Theres no real need for a 8-pin really, for most AMD CPUs, it really doesn't need the extra power. For that case of the Q6600, it is highly unlikely, unless his old PSU was horrible and it was undervolted.
But if you really want a 8-pin CPU, here is probably the most appropriate adapter to use. http://www.newegg.com/Product/Product.aspx?Item=N82E16812706006&cm_re=EPS_adapter-_-12-706-006-_-Product