Oc'd the 4870 X2, great results!
Edit: I took a look back at mine and compared to yours my card is really holding my score back. My CPU was 26k when my card was only 17k. The card in that run was only at 777core and 900mem so I will try and push it past 800 and see what I can do.
Try same clocks as me, 825 core and 950 memory, and just for fun you think you could run it at 4.3ghz? That will give the best comparison I5 VS I7 920.
My highest score so far is 20265 sorry I can't take a SS my print screen button does not work for some reason. My GPU score is 24699 and my CPU score is 13172