Thats too high for idle especially with that modest OC.
First check the reading is correct by using more than 1 utility to check it. If it is check your board is not auto volting the CPU it may be volting too high. Finally try stock speeds at 6 cores see if that helps. If that doesnt try stock then OC on 4 cores if thats ok but 6 aren't you have a bad core.
*edit* also check the cooler is on properly maybe take off clean add new paste then reseat