I don't like doing that.
I didn't see any improvements on the last one I did before it died of the ailments it already had. Although that chip just ran so hot it was unreal when I added any volts to it. It was reporting stupid temps like 30-40C when every other chip would have been -10 at the hottest. These single cores stay below zero even with 1.85v on the chiller unless you were benching, but I wouldn't bench with those volts.........maybe 1m