E6600 Tcase much higher than Tjunction

[sskings]

Per the excellent post http://forumz.tomshardware.com/hardware/Core-Duo-Temperature-Guide-fto...t221745 and others, one should expect Tcase +15C = Tjunction. My machine shows the other way around. At idle Tcase = 51C, Tjunction = 37C. At 100% load Tcase = 64C, Tjunction = 54C. Does anyone have any ideas on how to treat this? What do I believe when overclocking? Should I RMA the CPU? I'm using EVGA 680i and have had two boards give same temps.

Thanks for your help.