Ooh, this is helpful. Thanks.I've done a moderate, yet stable overclock with my 2070 Super that didn't require raising the power limit of the GPU. I get a little more FPS than I would with stock settings, and GPU temps have never hit more than 64 degrees with a custom fan curve active (though I'll note that I do have a case with good thermals).
In MSI Afterburner, all I did was increase 2 values: Core Clock to +110 and Memory Clock to +800. If I didn't mind more fan noise and extra heat, I could push this a bit further, but I'm happy with the results, noise, and temps.
Stock settings for the 2070 Super are boost clock at 1770 MHz and memory at 1750 MHz. Now I'm at 1880 MHz for boost and 1950 MHz for memory. Going higher without raising the power limit and/or messing with core voltage resulted in instability. Due to silicon lottery, your results will vary. Presuming your PC case isn't an oven, you could start with low settings, such +50 to Core Clock and +400 to Memory Clock, benchmark/test for stability, and go up in small increments/as far as you are comfortable with.
If you want to read more details on pushing a 2070 Super further, here's a useful guide.