1.52v is the maximum VID that is expressed in binary, that the CPU can accept a signal from, using the VRD 12 specification (possibly WRONG, see below). I believe someone said that the vcore the chip requests at auto voltage is the voltage it requests to run at at that frequency, based on that specification.
This has NOTHING to do with "Absolute maximum" voltage.
If you remember on the c2q 45nm chips, maximum VID was 1.3625 while absolute maximum voltage was 1.45v. Notice max VID is LESS than absolute max vcore. On the datasheet, the VID went up to 1.600v, but this was simply for the sake of completeness when entering binary bits as 1 or 0.
On 45nm i7, maximum VID was 1.35v while absolute maximum voltage was 1.55v. (proof here: http://download.intel.com/design/pro...hts/320834.pdf )
Now on sandy bridge, maximum VID is 1.52v, while absolute maximum voltage is...(unknown).
Now I honestly don't know why the maximum VID is 1.52v here. This doesn't make sense. Both previous processor families (C2Q/wolf series and core i7) had max vid around 1.35v.
I suggest you guys look at this carefully.
Go back to the core i7 chart for 45nm.
Notice in the vid CHART (3 graphs), the maximum VID possible that is shown in binary is 1.600v ?
But the maximum VId allowed for the processor is 1.35v? (minimum is 0.825v)
Now look at the SB chart here:
Both the CHART and the vid range ENDS at 1.52v, and starts with an ungodly low voltage of 0.25v. . This does NOT happen with previous processors, except for the binary VID chart, which is not a proper VID range for the processors. Something doesn't match up correctly here. Almost seems like someone made a design error making the documents, and made the VID range match the chart, which is clearly not what is supposed to happen. For proof, look at the 45nm I7 vid range: it starts at 0.825v at minimum. A processor can actually RUN at this voltage. But Sandy Bridge starts at 0.250. Good luck making any processor operate at that voltage, even under LN2. Someone clearly just copied the Binary field for vid range from the chart, and no one actually put the VALID proper vid range for the processor. (Willing to bet its about 0.825v-1.35v).
I'll bet anyone hard cold money that 1.52v is NOT the "max vid" for this processor. Unless you want to prove to me that 1.60v was the max vid under valid vid range, for the i7 45nm. Anyone care to take me up on that?
Unlike some of you guys, I don't have higher ups over at Intel, so me contacting them may do nothing...