Hi,
I have just finished overclocking my i7 950 to 4.2GHZ and after running Prime95 for 1.5 hours at an ambient temperature of 22 deg c, my cores peak temperatures were 74, 72, 72, 69 using Real Temp.
Voltages - vCore 1.31v - DRAM 1.60v - QPI 1.35v - CPU PLL 1.80v
My case does have a lot more...