I run a Asus M3A78-T with newest 2001 bios. I agree that there is no turbocore option to be found.
In order to disable turbocore you have to use AMD OverDrive. Go to the Clock/Voltage control, Un-select the radio box left to the turbocore control button, next go into the turbocore control section and unselect the enable turbocore radio box. Finally apply settings. This has to be done on every startup!
As for you overclock you are at about your limit for the 4-1 power phase design of the motherboard using a X6 @ 3.6GHz. I was reading X6 @ 4GHz uses like 224watts which is way outside the motherboards rated 140w support.
I just got a 960t which my board won't unlock so I'm stuck at 4 cores. Coarse testing so far I seem to get about 3.9GHz definately Prime95 stable at 1.42v but still dropping vcore on fine testing. 4GHz at 1.45 seems unstable though and believe it to be a limit of the board without extra volts. According to AOD OC testing it clocked fine up to 4.38GHz but that would never be prime stable i'm sure.
EDIT: Kill me, I necro'd a post. SORRY!!
Edited by roguetrip - 1/17/12 at 6:23pm