Seriously, DDR2 to DDR3 change doesn't get THAT much better performance. my 8GB DDR2 at 1120MHz 5-5-5-15 does fine for me. Of course it would be better performance with DDR3, but it's not worth the "upgrade".
The more i can squeeze out of this board, the better. And of course a bios change can do much for OC.. especially when it's a new cpu.