I'm running an HIS 7870 GHz edition at 420MH/s that I picked up on craigslist for $180.00.

Miner Settings:
GUIMiner 2012-11-18
-v -w 128
CPU 0 (i uncheck 1,2, and 3 because I'm also mining litecoin on the same box @30KH/s)

GPU Settings:
clock: 1155 Mhz
mem clock: 350Mhz
fan: auto
voltage: auto
temp = 65c