Throttling at 80c? What are you on about. Throttling doesn't occur until like 102c core temp.
Not sure how keeping it under 70c in prime should work out, by the way. Im reaching 75c in prime on stock speeds with a scythe mugen 4, which is considerably stronger than a 212 evo. That would mean everyone without a high end cooler is arsed.
Unless you were talking about prime without avx2 instructions (version 26.6 or lower). Then I agree.