I know nothing about cross-firing or sli, so excuse me if I sound stupid in this post. I want to know if it's possible to crossfire an on-board video with a PCIe 2.0x16 video card. The board has ATI Radeon HD 3300. The video card would be an ATI Radeon HD 4350. Do both video chips have to be the same, like two 3300's or two 4350's?