sportsfanboy :
You damaged your card by not upping the voltage and keeping temperatures cool? How is that possible?
Actually I've damaged 3 cards in the past, the best way for me to describe my statement is simply it probably did have something to do with temperature but not the GPU temperature that was reporting everything was OK. All those cards had no way of reporting what the temperature of the memory was getting to, and increasing the memory clock was increasing the memory temperature. I thought all was well from my GPU temperature as it was in the green, but that was a false confidence as running the memory at higher clocks was increasing the memory temperatures, which didn't show up as a problem until the artifacting while gaming began.
I'm sharing my own personal experience here and just saying it is possible, to give the OP another point of view, I think it's great you've had no misfortune in any of your GPU overclocking, but if and when you do, you may end up being cautious too. My statement is not meant to discount any advice you've given, it's meant to add to your knowledge that damage can occur and has occurred to others.
Caution should be the rule of thumb when it comes to any overclocking, unless a person has so much money to blow, it doesn't matter if they risk hurting their new toy.
@arthurh, Great explanations there Art!
@sportsfanboy, Graphics card manufacturers are mounting much better heatsinks today that cover the memory chips better than in the past, the past best results I ever got was going with an aftermarket cooling solution that would also direct airflow downward to cool the memory and voltage regulators on the card.
My best GPU memory cooling results were from making my own memory heatsinks and Thermal Adhesive bonding them directly to the memory chips, [Definitely Voids Card Warranty], but very effective.