I haven't tuned the software on these rigs for minimum overhead and I haven't overclocked the video cards yet either. Currently the farm is running at ~6GH/s or ~500MH/s for each 7970. I built it as fast as I could to get the mining started so they are currently running Ubuntu desktop. Ultimately I plan to create a Gentoo USB install that automatically tunes and mines each rig.
Link to imgur album
Link to imgur album
How much did all of that equipment cost you, and when do you count on recouping your investment? It amazes me that people still buy GPU:s for mining. It's a very risky venture that will most likely never pay off.
i suspect that there are still people who want to mine BTC with expectation of holding them til the value increases
didnt you read the post about each BTC being worth 13k 