thread-concurrency is only for scrypt mining right? 

I'm bitcoin mining currently.  Just compiled and installed cgminer.  no love...   i'm wondering if it is a BIOS setting or something...   I tried different pools, different miner programs, changed a bunch of settings.  not really seeing a difference.  Either card works well on it's own.  Getting about 450 - 500 hash from one card mining by itself, which is good for a 7950.  Once I activate the other card the hash rate drops...   Wish I knew what I was doing wrong. 

Rock