I had one similar that did 3.6 with Bios vore 1.5 on a P5W DH - its had a vdroop of .025.Try it with the settings I posted
http://www.xtremesystems.org/forums/...&postcount=873 with these amendments , CMOS=9, vcore =1.5 and FSB=1.3v and see if you have any joy. Course not all e6600 would do 3.6 but most of them could get there with a bit of encouragement. If not 400 try 390 then 380 etc.
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