Well this all dapends on your system and temps. I'm doing 1,350 with no volt mod and 630 on the memory and i'm safe.

If you want more then a +135 on the ore you need to use nvidia inspector to force a pstate but keep in mind your card will not throttle any more and will be running full power the whole time so temps will go up. been seeing clocks from 1,100-1,200 most people get and the better gtx 660m's are hitting over 1,300 on the core. keep in mind these are all without volt mods.

I would back off the memory and oc the core first then do the memory because your memory clock can affect the core's headroom for overclocking.



Now i will say going from stock to a 1050 on the core i did see in some games a gain of 20fps. Now i haven't tested that in crysis or anything but in the few games i did test kepletr is scaling pretty nice with the clocks.



My advice is to check out.

http://forum.notebookreview.com/gaming-software-graphics-cards/677169-nvidia-mobile-kepler-6xx-maste...

Then clock 20-50mhz higher at a time and check for stability, artifacts and your temps. If you get artifacts or bsod's then back off the clock by about 20mhz but 1,100 on the core should be pretty easy for you to get.