I have the same cooler, but 4670k. By using P95 also getting those temps at 4.5GHz @ 1.29V. Prime95 tends to overvolt the cpu, 1.29v was manually set and was going to 1.36V. That's why I now use AIDA64.
Well I was hoping you'd list the memory speed so I could avoid typing a bunch for nothing, but since you didn't I'll just say if you are running memory speeds past 1600mhz, you are actually overclocking the CPU memory controller and adding heat.