I wanted to run my monitor off the integrated motherboard graphics, and devote my 7850's to pure mining. I can direct my BIOS to use the IGD. And my two 7850's even show up in gpuz. But cgminer says it doesn't detect any graphics cards.
Motherboard is MSI Z77A-GD65 GAMING. They stopped selling the vanilla Z77A-GD65. Latest BIOS.
Are you using sandy bridge or ivy bridge?
Also, I'd recommend reading
https://bitcointalk.org/index.php?topic=87611&
https://bitcointalk.org/index.php?topic=186439.0