Voltage scaling and “1.25V limit”

There were some rumors spreading wildly these days regarding “1.25V limitation” or whatever on modified GTX 1080 cards, which requires here few words to explain.

Hardware itself is well capable of getting to that and above voltage output for GPU core, but GP104 GPU itself is more sensitive to voltage than previous generations. Part of it due to thinner physical process, other part due to difficulty of removing heat quick enough from all those tightly packed 7.2B transistors from 21% less surface area. Those overclockers who did 2.1-2.2GHz on GTX 980 Ti’s are aware of all the things required to achieve those high clocks. Same here applies to Pascal generation. So if you can manage to keep GPU cooled well and have good voltage delivery to it, you indeed can push higher voltages. Cards cooled by liquid nitrogen during this guide testwork were able to run 1.35-1.4V, reaching speeds over 2500MHz.

This also brings and answer to the question if overvolting can help OC on aircooling or watercooling. It does not help, due to thermal, which get only worse. Higher temperature render stability and performance decrease. GPU literally overheats and cannot run high frequency anymore, even though temperature is below specified maximum temperature. So just like in 980/980Ti/TitanX case, overvoltage is not recommended, as it gains no performance improvement.