specialservice
I managed to get it to 2164 while folding however I had to crank up the GPU overclock a LOT! I don't remember the actual offset but I was surprised it didn't crash. The temperature went up about 3 degrees as well, these cards are interesting as they take a large amount of gpu offset once you pass a certain threshold for very little gain.
It seems with Boost 3.0 and the way the Pascal cards control the gpu clocks that the offset settings you make in Precision X OC or Afterburner are merely suggestions. One other thing: the offsets allow very specific numbers, like +137 or whatever you type in, yet the gpu only increments its speed in steps of 12.5Mhz. So you may try +130, +135, +137, +139, etc. and not see another actual bump in speed until you cross the next multiple of 12.5 in speed.