This is clearly offtopic(sorry OP), but would you be so kind to share the parameters you used? I can't manage to get above 380 out of my 7870 XT. What a bad purchase!
What saves me is the used 6950 I got for 80. After the bios modded, it gives me solid 490 Kh/s
I don't mind helping another miner out .... my settings are:
-I 13 --worksize 256 --thread-concurrency 8000 --gpu-engine 1175 --gpu-memclock 1365 -g 2
With fan speed set to 80% I am running at 76 degrees, wish I could afford a better second GPU to throw in my box, geforce 9600gt doesn't cut it for mining, on a plus note though, I can still play diablo 3 on my mining rig using the second card

. Hope this info helps,
Sparhawk