Yeah, I would re try the thermal paste.
The IB cpus are known to run hotter just due to having thermal paste from the cpu to heat spreader and not the older welded(soldered) heat spreader.
I would not be surprised if it has to do with that.
On that note, I had a 955 BE(only 3.8 GHz if I remember right) and it did run cooler then many of my intel builds.
The I have the most crammed case in the world with my coolest running chip(i5 750)