Okay this is weird.  Wondering if anyone else has experienced this.  Have four rigs mining monero.  Three have 2 card with ~1700 hashes each, get around 3500 shares every 30 minutes.  The fourth rig has 6 rx470 at ~3600 hashes, but that one only shows ~1500 shares over 30 minutes.  That's like 1/4 the of the shares the other three rigs do.

If run three instances of claymore with 2 cards each, my shares increase to nearly 5500 over 30 minutes for each of the three instances of two rx470 each - just ~1200 hashes a piece.

Why would running more cards produce fewer shares than running the fewer cards in more instances of claymore?  I've been running these for a few months now - have no idea why...