@bensam1231
I have the 980's undervolted, which has so far proven to provide about the same stability ceiling, while driving less power and heat (so yeah, I'd expect that overvolting would tend to lower the efficiency). Standard voltage at top clock bin is 1.125v IIRC, while mine are running at 1.112v.
I don't have any 750's anymore, but I do recall those behaving very differently. The ones I had before, would allow quite a bit more overclocking if also running overvolted - but on those - I was not bound by thermal or TDP limitations (which I am on the 980s).
The issue with running the cards very hot (near the specification limits) is not one of killing the cards in an instant. They are certainly designed to manage the temperatures for long periods of time (hence the thermal throttling). The issue is that, cards that always run hot, will tend to have a shorter lifetime than those than always run cool.
Manufacturers are also not stupid. They will be happy to have a good number of cards failing after some 4 or 5 years of abuse, so they can sell some new ones
@SP_
980 @ 1370, 3505 - quark
release 44 - 19.2MH/s
release 51 - 19.5MH/s
