I will let you know that personally I do not like Wattman just because it's very user unfriendly to me. I have used it and thought that I was doing well with it. However I got better results using MSI Afterburner. As far as your issue, are you trying to max everything out? Cause if you do that I can guarantee you that Wattman will look at that and say, "WTF HELL NO!" and revert it back to stock.
Ya I was going to say the same thing. Unfortunately it sounds as though you don't know exactly what you are doing. I would read up and learn about how to overclock a GPU before continuing.