about E6600 overlocking temp

[nn2000]

I got two different temp degrees when overlocking e6600 to 3.2G with stock fan. It is 55c when overlocking as 9*356, and 65c when 8*400. Why the latter is higher?
The other question is that both the temp degrees are higher than the average, any solution to make it below 50c?

 

[imported_yes]

I can't answer knowledgeably about temp rise based on FSB change. But, I hope the voltages were same both times and same activity type/level were happening. The second question is easy buy yourself a decent air cooling fan or water cooling. The choice is again there between cost and how much OC you want to do. Thermalright, Zalman, Arctic Cooling come to my mind as air cooling fan options.