Your load temps are kind of high for that oc and voltage,for a stable oc of 4.7 to 4.8 majority of the chips need 1.35 to 1.40v mines at 4.7 with 1.38v idle temps 24 to 26 load max 60 to 62 using a silver arrow
Yeah my temps were a bit high; mind you the PC is without ambient air-con. I would say that ambient temps would be around 24 degrees celsius though. You'd think given my cooler that the temps would be lower. I do have a DEMCiflex front filter on the Corsair 650d case though; that may be restricting air.
For you to get 4.7 at 1.38v did you just alter the vcore voltage only? And, what is your ambient temp?