question: I'm using 2x opteron 6376 and get around 475 h/s using 16 of 32 available cores which seems to consume about 57% of CPU resources. Could i tune this up to get better performance and also use the other 16 cores? Thank you for any comments or suggestions.
What coin/algo?
The Opteron 6376 is basically two AMD FX Piledriver dies on one package. An FX 8300 hashes around 1000 H/s Cryptonight-Lite or 340 H/s with CN v7.
Your system with two Opteron 6376 (say four FX dies), but lower frequency, should be around FX-8300-hashrate * 4 * 2.3 / 3.3. So CN v7 hashrate should be
VAGUELY 900 H/s for the whole system with optimized settings

But that depends on what coin/algo you want to mine

How would I determine optimized settings? I guess I should see what I get on CN v7 to see if it's close to that 900 number. any suggestions of coins to try? Sumo?
I didn't know that about AMD FX Piledriver dies. Your response is very informative. Thank you for that.