I have an EVGA GTX760 that I am trying to overclock, I am overclocking using EVGA PrecisionX and benchmarking with Unigine heaven 4.0 extreme preset. After reading some articles about overclocking and some videos, I was under the impression that the highest memory clock offset realistically possible was ~400, maybe 500MHz. However I didnt get a crash in Heaven until 810 MHz offset on memory clock. So far the large increase in memory clock has given a small increase in framerate.
My question, is +800MHz memory clock offset putting the health of my GPU at risk?
You always start the overclock with core clock. When you achieve the highest stable core clock rate you can, then you start with the memory clock as a final tweak. Memory is usually pretty sensitive, go only a few mhz at a time with it. As you are finding out, memory speed does not have a big effect anyway.