Im using the following cgminer command:
c:\tools\cgminer3\cgminer.exe --scrypt -o [pool] -u [username] -p [password] --thread-concurrency 6144 -g 1 -w 256 -I 13,13
first card is my HD5850, second card is my HD5850 - i will be adding in my HD 6850 soon and converting to an open air case using this:
http://www.amazon.co.uk/Lacewing-Tier-Mini-PVC-Greenhouse/dp/B008J26F9Gthe PVC is long gone and the botton shelf got broken.
I'm building a custom motherboard mount and I have 3 powered PCI-e x16 extenders and 2 220mm InWin case fans that i will use to blow into the front with the cards pointing out the back.
the artifacts go as soon as i disable my second monitor so i assume that something is a little damaged.