One actually hashed slower in High mode: Low: ~32Gh/s High: 29Gh/s. Now it's running at 33.5Gh/s (now most likely limited by one card that has 8 X's on High)
Is it 8 scattered X, or 8 together? Probably an undervolt condition on that bank's VRM; I can think of a few possible causes most of which I could probably fix for you.
It's 8 all together on the right side. Anything I can do? It's hashing at ~34.1Gh/s now btw.