I recently got a intel Nuc 11 Essential NUC11ATKPE with a Pentium Silver 6005 and i want to undervolt the cpu but i can’t figure out how on earth intel has locked it down so i can enable FIVR control again.
First of all the UEFI bios region has Boot Guard enable with Verified boot and the FPFs set so this means that changing any byte in the protected DXE sections will brick the thing so i cant unlock any of the hidden bios settings but i can still edit the values in NVRAM using RU and the IRFExtractor so i set “Overclocking lock” to 0 “CFG Lock” to 0 and “Overclocking Feature” to 1 but in ThrottleStop FIVR section still says Not available in voltage control so reading more about this i discover that Intel blocked the OC mailbox MSR 0x150 in some CPUs because of the Plundervolt vulnerability and nobody on the planet apparently knows how to enable voltage control again.There is also a FIVR Configuration section in the bios setup that might be useful.
Can someone help me to enable voltage control on this cpu please?
Last but not least i have a SPI programmer so if someone has some crazy and risky idea i’m willing to try.
Yes already did disabled the Overcloking lock using Ru.
Here is the setting in the text file obtained with IRFExtractor:
0x2F6D3 One Of: Overclocking Lock, VarStoreInfo (VarOffset/VarName): 0xDF, VarStore: 0x2, QuestionId: 0x210, Size: 1, Min: 0x0, Max 0x1, Step: 0x0 {05 91 09 04 0A 04 10 02 02 00 DF 00 10 10 00 01 00}
0x2F6E4 One Of Option: Disabled, Value (8 bit): 0x0 (default) {09 07 04 00 30 00 00}
0x2F6EB One Of Option: Enabled, Value (8 bit): 0x1 {09 07 03 00 00 00 01}
So i use Ru to change the byte 0xDF to 0 in the VarStore 0x2 which corresponds to the CpuSetup section of the NVram but voltage control still not available and i thick that the developer of Throttlestop said that Intel locked down the voltage control of some Cpus by blocking the read and write access to the OC mailbox MSR 0x150 register and i just can’t find anywhere on the internet how exactly they did that so i going to assume there is some top secret NDA going on here.
Maybe in the FIVR Configuration in the bios setup there is some setting that can enable voltage control again.
