I've had 2138mhz stable on an EVGA GTX 1070 and I have 2100 stable (peak) on my current GTX 1080.
Now, the 1070ti is a cut down chip and not a top bin part so it may be different, but as always YMMV. 2000 mhz however should be in the cards for almost every Pascal GP104.
The real key to Pascal overclocking is getting familiar with GPU Boost:
- It starts dropping 13mhz 'boost bins' at every 5 C interval from I believe 55 C onwards. Temperature is therefore a huge factor in what you can hit.
- Because its so temp sensitive, lower voltages may offer better sustained clocks. In the end, a high OC is only worth it if you can keep it going. With my 2100 mhz peak setting, I do drop down all the way to 2000mhz because of temperature over time. Your real OC is actually thát clockspeed. The peak is nice for benches, but that's it.
- EVGA's Precision X offers a fine grained OC control that allows you to set a voltage for every temperature target. If you want to push it, especially on air, this is what you need to be tweaking with. The gain however is going to be extremely limited over a 'simple' overclock. (13-39 mhz, simply because you can hold your boost bins a bit better)
- While temperature is key, there is still a hard limit which is voltages. No extensive tweaking involved, if you have good temps, knock the slider for extra core volts to the right and start testing clockspeeds.
- 1070ti benefits a lot from memory OC, especially in min. FPS. You should be getting an extra Ghz out of it usually for VRAM.
On STOCK voltage and power target, you can start with +100 Core and +500 Mem. If that sticks work from there and use +20 steps on Core, rebench and see if you still gain performance (= points!). I use Unigine Valley for this 'quick OC'ing; it will crap out fast if you overdo the core clock and has very consistent scores, so you can quickly identify if its worth to keep pushing.
As soon as you hit instability (frequent stutter, artifacting, or lower scores), add +10% to Power Target. Rinse and repeat until you have nothing left to give. After maxing Power target, you can go further with unlocked core voltage in the same way. If you get lower scores at higher power, reduce core by -20 and use the lower power target before scores dropped = done.
Doing it like that keeps you away from excessive temp throttling. If you smack down max voltage right away, you have no idea what lower volts can do. When you found your max overclock, run it through 3DMark Firestrike a few times. If it holds, you're stable enough. If it crashes, reduce Core OC by -10 or -20 and retest.
