Hey man- out of curiosity how old is the system and gpu? And has this always happened since you got the card? i have had similar issues, posted a thread and everyone seems to find a different solution to their problems.
Other things to try:
1) Put your whole windows on a separate drive and make sure you have the latest drivers, you don't want to go too far back in driver version as you will start to get conflicts with windows etc.
2) Try changing the cables, its worth it just to test and know.. my brother was having a similar issue and changing his 8-pin cpu power sorted everything out
3) have as little other crap running in the background. I am almost sure my problem was actually HWinfo64. When i had the program running to check all my voltages and temps etc my pc constantly crashed, but without really adjusting anything i have no had a problem since not opening the app. i have deleted and reinstalled but haven't had time to see if that's worked yet.
4) Make sure you haven't got two different programs open trying to dictate the OC (e.g: Msi Afterburner and Asus Aura). I know some cards RGB you need there own software, but if you have MSI afterburner (Think this is the GPU OC'er of choice) and the RGB software it might be conflicting as the RGB software generally has an overclocking manager on it. could be conflicting.
hope something here helps you and stops you from having to do RMA..
