I just bought Galax GTX 1060 6GB and indeed its memory using Hynix. I've tried overclock / underclock and maximum results are 300-327 Sol/s in Equihash. My settings are:
power limit 90
temp limit 75 (manual)
core clock +225
mem clock +575
fan 60 (manual)
power usage 105-110W (ewbf)
eficiency 2.8-3.1 Sol/W (ewbf)
temp 66-70
UPDATE:
efficiency >3 Sol/Watt, reduce power limit to 85
+225 on core? That's pretty high. What's the effective clocks while mining? That's what matters though.
Afaik, equihash need core speed instead memory speed.
Update config:
Power 80, temp 70, core +200, mem +400, fan 70. Got 295-310 Sol/s with less than 100 Watt.
Equihash does need higher core speed but at 80% power limit you're already lowered the voltage applied to core. So that +200 core bump isn't actually doing anything with realtime clocks. Check the actual clocks while mining.