Totally depends on your card if tweaked a little but to be honest mining ETH even overclocking cards you don't see much improvement other than more heat and kwh used. Found that out already on R9 280x cards.

You can however play around with the following settings --farm-recheck 200 --cl-local-work 256 --cl-global-work 18432 found to be bout the best setting without giving away other settings that I decline to provide. You can play with recheck global and local work to find maximum sweet spot takes a lot of work. Global work you can increase by 1024 each time and find max setting card will cope with. I am taking a wiled guessing this is just like intensity of how hard  card is working. I do remember use to do something along lines when mining LTC a while back and playing with same settings to get a good work load, balance and good hash speed. Will take a while to work best settings out for your card testing and moving up the ladder and finding that sweet spot. Once done just remember to note settings down and save for later configurations for other crypto in future