I think the new patch really pushes the grafikcard above its limit.
Possible reason: Overclocked Cards, by the manufacturer, hit their TDP limit due to unknown ffxiv calculations/commands and the driver won't let them to use higher Clocks then idle.
Power Control raises the TDP to increase the amount of voltage the card can use when under load.
I only ask myself what is square enix calculating with the recent patch? Feels like Bitcoin farming.