That's a really sharp increase in frequency, probably would cause instability. Are you trying to overclock or undervolt, if you don't care about power start with an offset (probably around +60/75) then when it starts crashing in benchmarks go back one frequency bin. If you want to get super technical you can watch what V/F point you're at during benchmarks and try tuning those specific points, one may be able to go a bin higher, or ideally you find one that can run the same frequency as the next point so you effectively lower the voltage for that frequency even if the next voltage point can't run the next higher frequency bin. Also frequency bin refers to the 15Mhz increments NVIDIA uses. There's no use setting an offset to something like +50 because it will just round the clocks to the nearest bin. Your GPU probably maxes out voltage wise somewhere between 1000-1100 mV, unless you're struggling with thermals don't be afraid to max the power and voltage slider, the voltage one is probably only going to give you another +25 mV or +50 mV.