overclocking GTX 680: help please

[stein]

okay so i am new at overclocking so i could be doing this wrong but here goes. i am using evga precision x as my overclocking tool, i started out by setting the power target to the max at 131%. then i started increasing the GPU clock by increments of 20. each time i tested it by running unigine heaven. if it passed i kept increasing until i found 155MHz was the highest i could reach. i repeated the process again but did the memory clock this time, reaching 555MHz, i compared the scores i got and found that i got a higher score with the memory clock. next i started increasing both the memory clock and the GPU clock together and i kept seeing my score and average FPS go up. until i got to a point where the scores and FPS started to go down significantly i rest to default settings and ran the benchmark again but the FPS was still much lower than normal. after a turning everything off and leaving for a few hours i started back up and ran the benchmark again and everything was normal. did i overheat the card by doing multiple benchmarks back to back? or did i push the card too hard by increasing the GPU and memory clocks to high? should i just leave it alone at default? can i cause permanent damage if i try to overclock again? thoughts, comments, advice would be greatly appreciated.

[hiyayhi]

A card sometimes gets "burned in"

Was this a new card?

[Brendan]

Well, first off you should overclock with increments of 13mhz for core. 20 won't make a difference and it'll just round off to the lowest 13th increment. I find that 555mhz on memory is probably too much aim for around 475 when benchmarking.

Which brand and what type of 680 is it? Lightning, superclock, FTW, etc etc.

[stein]

i have had the card for just a few months, and the brand is EVGA and its the FTW.