I am using an Atom N2600 processor. The intel software developer's manual says that a p-state can be requested by writing to MSR 0x199 and the locked p-state can be seen in MSR 0x198. The way to compute Core Voltage is given as MSR_PERF_STATUS[47:32] * (float) 1/(2^13).
The data that I see in MSR_PERF_STATUS (MSR 0x198) is 62d104306001045. Bits [47:32] is always 1043 irrespective of the value that I set in MSR 0x199.
When I use the formula: 0x1043 = 4163. Voltage = 4163/(2^13)=0.5 V, which is a really low voltage for the processor to operate stably at.
It would be great if someone can help me in measuring the core voltage. I am using Ubuntu as my OS.
Regards
Srinath
