Question about BIO

[Csst]

The question i have i think i might have found out what my problems is, but i want to ask the advice from you people to see what you think i been stuck at 3.5 ghz with my X6800 and have eveything pretty much at stock setting like Vcore 1.325 and everything else at auto .(temps not a issue using water cooling idle at about 39 40 and under full load around 49 or so) Now i have try changing thing to try to get it higher like moving my Vcore to 1.425 and moving my MCH to+.1 vdimm and FSB all to +.1. and i set my memory timing Manual to the factory which is 5-5-5-12 and still can't seem to get any higher. Boots into windows just fine at 3.6 and even 3.7 but the problem is i run a stress test and it stops after about 20 secs. Now after reading do you think this could be my problem why i can't go any higher? i notice in my BIO there a option which says CPU Enhanced Halt (C1E) that was enable also there another option CPU thermal Monitor2 (TM2) also was enable CPU EIST Funtion was also enable. Now should these stay this way or should all or any be changed to disable? And do you think this could be part of my problem not being able to get any hiher than 3.5?