Burned up my 3870 video card and wanted to replace with the cost efficient 6850. My motherboard is a k9a2cf and has a 2.0 slot. All the new cards are 2.1. Is this a problem. I googled several times to no real answers. Messaged MSI but awaiting a conservative answer along the lines of "the board was not made when the cards came out" type of reply. Thanx in advance for any help.