i have two 980ti g1s. The first one was awesome. Did 1520mhz on air with very small voltage bump and i live at 10,500ft in elevation where air cooling doesn't work for shit. Could have gone further at sea level for sure. I put it on water and it does 1595mhz.
My second g1, pos. 63% asic wouldn't even do 1500mhz on water. Got pissed and put a custom bios on it and it now limits my oc to around 1525. Never bothered to find out what it'd do with the stock bios. Their binning process leaves something to be desired imo. These were my first non evga cards. Will be going back to evga for pascal simply because of their warranty.