I am building a gaming pc with a amd fx 8350, msi radeon hd 7870 OC, and a MSI 970A-G46 AM3+ AMD 970 SATA 6Gb/s USB 3.0 ATX AMD Motherboard with UEFI BIOS. I am planning to buy a msi radeon hd 7950 in the future. Coud i crossfire the 7870 and the 7950?