IMO that seems high on both the stress test and when gaming. I have an I5 cooled by a Hyper 212 at 4.6 Ghz at stock voltages and it idles in the low 30's. When gaming it goes into the 45-50 degrees. Under a Prime 95 stress test I think it was in the 60's. I would make sure the heatsink is on right and fully secure. If that doesn't work I would re-apply thermal paste.