I changed the program I am running from guiminer to cgminer and increased my hashrate by 10 mhash/s per card that way.

Is there anything I can do to increase my hash rate at this point? Or is this rig just going to be stuck at this rate, 20% below target?

Here are my cgminer settings which I copied from the forum:

"intensity" : "9",
"gpu-engine" : "0-1125",
"gpu-fan" : "0-85",
"temp-cutoff" : "90",
"temp-overheat" : "85",
"temp-target" : "75",
"auto-gpu" : true,
"auto-fan" : true,
"expiry" : "120",
"gpu-dyninterval" : "7",
"gpu-platform" : "0",
"gpu-threads" : "2",
"log" : "5",
"queue" : "1",
"retry-pause" : "5",
"scan-time" : "60",
"temp-hysteresis" : "3",
"shares" : "0",