There is absolutely nothing in the stock bios that will allow you to hurt that GPU. Slide the power limit all the way up, increase the voltage slider all the way up, and start bumping the core up. Once you find a core clock that you're happy with, and that's stable, then start bumping memory up. Rinse and repeat.
Using a benchmark to test stability can give a pretty decent feel for what's going to work, and what won't. Unigine Superposition 1080 extreme, FS Ultra graphics test 1 and 2...I prefer the latter.