We're using the "Temp Target" trick I figured out to undervolt the cards even further than MSI Afterburner/PrecisionX will allow u.
You could probably downclock your memory to get more headroom for GPU overclock.
Please spread the word about our spreadsheet/survey combo:
Looking at some of the entries for my card (GTX 760), i find a couple results very suspicious. There's no way a 760 can get up to ~500 khash/s. 2x760 in SLI, maybe, but that entry doesn't have any sort of information. The most I've been able to get mine to get up to is ~300 khash/s, but it crashes after a while. Stable, about ~290-292 khash/s
I also don't see how you can underclock the GPU Memory Clock -442. As soon as I set those settings, it instantly froze and crashed (Although I don't know TOO much about OC, so I could be wrong on this part).
It needs to have some sort of moderation, or require screenshot proof of achieved hash rates.