I just recently found out by using GPU Shark that despite my Overclocking using the EVGA Precision tool, these cards were running in Performance State 8, which utilises under half the power i set clocks to.
Using the PowerMizer tool for Nvidia, I was able to set the PState to 0 and the cards are now actually functioning in an overclocked state ( I thought it was pretty odd that EVGA would let you set the clocks, and then through another momnitor you see they are capped in a Pstate under half of your settings..)
Anyway, The problem was originally that only 1 GPU was experiencing load after the change. After a restart, I can see that both cards are working through the temp monitors, but neither cards are showing the GPU usage in EVGA Precision, GPU Shark or any other tool.
Does anyone know why the cards would stop having their usage displayed?