Hahahah!
 I just changed intensity from 30 to 29.6 (#4) on my 980Ti rig and (minerside) hash vent from 7800 rising slowly to over 9700 (!)
Well, poolside : it's still 6.7 -  7.4GH (yiimp). Gonna watch this!
edit: hmm 5.2 GH.../quote]
Then at 29.2 I have 7.8 minerside, stable, and 8 -9 poolside also more stable. Looks like it's about sweet spot search. It's rig 1x980Ti extreme,2x980 Gaming, 1x960ixoc. All light clocked.
Actually at first minutes it hashes with lot green "yes" and later less and poolside drops also. Less so with 29.2 now.