Can only boot 10.11 with NullCPUPowerManagement.kext (And no other OS'es at all)

[Captain Crunch]

I have an ASRock Z68M-ITX/HT with UEFIPatch patched UEFI 2.41b

It's exhibiting some very strange behavior. Essentially, I can only boot OS X (have tried 10.10 and 10.11) when I'm using NullCPUPowerManagement.kext. OS X without, Windows, Ubuntu, etc all reboot quickly after the bootloader hands off.

When I'm in booting into OS X via Clover with NCPUPM it works well, Intel Power Gadget indicates power states, I've patched a SSDT, etc, but clearly there's something odd about this board that's preventing full functionality.

Here are two pictures of it booting just before it reboots without panic. Again, it works more or less perfectly with NCPUPM, but I'd love to solve the hardware bug and figure out how to boot Windows as well.

 

[P1LGRIM]

The P-State Stepper Error can be overcome by disabling EIST in BIOS.

 

[Captain Crunch]

Thanks - it's actually not a hang rather that's the last line that prints before the machine power cycles itself.

 

[Captain Crunch]

If I boot a Windows installer (7 or 10, UEFI or MBR, USB or DVD) it will get to the Windows flag loading splash screen, then reboot without any error message.

A similar result occurs when loading PartedMagic or Ubuntu.

OS X appears to be able to use all CPU cores, RAM, and graphics card power available to it in this mode.

I've attempted disabling C-states in the UEFI, rolling back to previous UEFI versions, and even swapping CPUs and RAM and power supplies.

In addition I bought a CH341A BIOS programmer to test that I'm writing a checksum validated UEFI file to the BIOS chip which I've confirmed that I have.

At this point I'm wondering if there is some power management hardware that's unable to initialize at some point after POST. Is there a specific set of CPU pins on the 1155 socket that I should check for damage or bends that might be causing this?

Is this possibly Intel Management Engine firmware related? Is there a way to disable power management in Windows when loading the installer?

 

[Captain Crunch]

I actually found I can boot Windows normally if I enable the C1E State and limit Package C State Support to C2 in UEFI.

If I enable C3 or C6 it causes the sudden reboot. OS X is still unhappy without NullCPUPowerManagement.kext, and I tried a patched AppleIntelCPUPowerManagement.kext for Sandy Bridge but it also did not work.

So, it looks like the problem may have to do with switching on the hardware C3 state? Does OS X probe that when it's booting?