So I sez the GPU, run faster, and then it did.
But seriously, lately been playing with power targets to see if I can drop a few degrees off my 1080. No issues running itself up to 133% power target (supposedly it should stop at 120%), but that could just be bad logging. Pretty standard fair though I can only eek about 2101Mhz out of the GPU and something like 10,400Mhz out of the memory. Not bad for a reference design board, but not amazing.
I think GPU overclocking has become a rather tame affair with Nvidia.