toms link.
It is not temp downclocking. You can see these options in the bios screenshots as well, on the EE edition you can override them.
What is hardwired into the chip, is it is limited to powerdraw as well, not only temp. So if you buy a i920, and you luck out, like i did with my q6600 and your tdp is way down lets say 72 watts for arguements sake, you ve got massive headroom and the volts would probably get to high before you reach that wall. However, there is a spread , like in all processors, so if you get an i920 that has 110W tdp at default volts you wont get very far before that wall comes into play. Since the i920 i would assume is the lower bins, the luck of getting a low TDP chip is not on your side, and this will otherwise limit oc'ing for a chip, that might have to be pushed harder than another.
The benefit or protection element doesnt make sense to me. If you have temp based down clocking.. i dont see the necessity for this, as you void your rma abilities if you go beyond spec anyways... so either they found a high inciedence in fried chips.. meaning this can't handle volts well (which i doubt) or they wanted to stop budget chips from getting up to 4 - 4.5 on air... it makes perfect business sense, just hoops us budget oc'rs who cant drop 1k on an EE chip.
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