I want to crossfire in my current system, and my current card is a MSI 7950 (two 6pin power cables). However when I went to look at cards many of them are 8pin + 6pin and my power supply (Rosewill Extreme 950W) only has two 8pin connectors free. These are not 6+2, they are solid 8pin connectors Should I go look into a 8pin to 6pin converter or can I plug in a 8pin connecter and hope for the best?