Mysterious UEFI Behavior on Biostar AM1MH with AMI v4 BIOS

[DeathBringer]

Change

Code:

0x390B5         Suppress If: {0A 82}
0x390B7             Variable 0x6 equals 0x0 {12 06 06 00 00 00}

to

Code:

0x390B5         Suppress If: {0A 82}
0x390B7             Variable 0x6 equals 0x1 {12 06 06 00 01 00}

One byte patch:
0x390B5 0A 82 12 06 06 00 00 00
to
0x390B5 0A 82 12 06 06 00 01 00

[DeathBringer]

Note that setting values in PState isn't set higher than full speed of CPU.
It's for power saving, not for overclocking.
You can't set multiplier higher than x22 for Athlon 5370
In first screen shot x36 is the maximum allowable value in BIOS.
Note that Universal IFR Extractor wrong interpret EFI_IFR_EQ_ID_VAL. Variable 0x6 isn't number of variable in VarStore, but QuestionId.

[Eschaton]

Note that setting values in PState isn't set higher than full speed of CPU.
It's for power saving, not for overclocking.
You can't set multiplier higher than 22 for Athlon 5370
In first screen shot you can see PState of previous installed CPU.

DeathBringer,

I think you are only confused by Biostar's bad naming scheme. Their P-State stuff IS their overclocking software on other computers. It's a bad name because as you say, it seems like you would choose it to set multipliers at different power states (p-states) - but this is not so. Instead it applies the multiplier only to the "standard" running P-state, which is pstate0. If you turn off Cool 'n Quiet or whatever the modern equivalent of that in an AMD system is, it will run in pstate0 (max speed) at all times.

While you cannot in theory set the multipliers higher for the Athlon 5370 because it is a "locked" chip, it can in fact be overclocked by multiplying the base clock (what used to be called an FSB overclock) in ASUS motherboards in this series. While changing the multiplier is not the same thing, I have some hope that this may work anyway, because of how this UEFI is behaving:

I know that the first multiplier is not the multiplier of the previous CPU because no other CPU has ever been installed on this system. Another thing indicates to me that it might actually set the multiplier higher - The first time I saw the higher multis, I set the CPU to the max, x36, to see if it would crash the system. It did - the system failed to POST. If setting the higher multi did nothing, then the system should post just fine and go back to a UEFI showing that it had set itself to the stock x22 multiplier. Instead after shutting down from the failed POST and rebooting, I booted to a UEFI telling me it had set the system to the failsafe x8 multi, indicating a failed overclock attempt had occurred. 

The actual remaining problem for overclocking on this board is just getting the settings to stick. To get the higher multiplier options to show again all I have to do is remove the CMOS battery, then put it back in and boot. If I choose a lower OC next time like x22.5, the system restarts and POSTs just fine, but the BIOS shows me set at default x22. That's the problem I need to see if I can change. The first step is making sure we can always see the higher multiplier and voltage options!

EDIT: More evidence that setting the multiplier for these chips is only a BIOS setting and not part of the CPU design:

• The 5350, another "locked" chip, can have its multiplier set from x20.5 to x21 in some motherboards in this series
  
• There are no unlocked "K" series chips in this socket, so AMD doesn't have to do anything to the chip design to make it locked; just ask motherboard OEMs to disable multiplier changes in the BIOS
  

Evidence that I might be wrong:

• The OEMs that do allow overclocking on this series use inferior (for SoC type CPUs) "FSB" overclocking. You would think if they could choose multiplier OC options they would have, but perhaps they were under contract not to allow that kind of setting in AMD's budget series?
  

I intend to get to the bottom of the mystery 

[DeathBringer]

You can set value of Core FID without BIOS editing.
1. Take USB stick and format to FAT32
2. Create directory structure EFI\Boot
3. Download and unzip bootx64.7z
4. Put BOOTX64.EFI to Boot directory.
5. Boot from this USB stick
6. Run command: setup_var 0x1
7. Make and post a photo of the screen.

[Eschaton]

You can set value of Core FID without BIOS editing.
1. Take USB stick and format to FAT32
2. Create directory structure EFI\Boot
3. Download and unzip bootx64.7z
4. Put BOOTX64.EFI to Boot directory.
5. Boot from this USB stick
6. Run command: setup_var 0x1
7. Make and post a photo of the screen.

Sure thing. Here it is:     

[DeathBringer]

OK. Now you can change Core FID by command
setup_var 0x1 0xXX
where 0xXX is
0x1C - x22 (2200 MHz)
0x1D - x22,5 (2250 MHz)
0x1E - x23 (2300 MHz)
0x1F - x23,5 (2350 MHz)
0x20 - x24 (2400 MHz)
etc

[DeathBringer]

Or you can try my mod of BIOS.

[Eschaton]

Or you can try my mod of BIOS.

Haha, you move too fast for me to learn everything you are doing!

THANKS though for all the help. I will catch up to everything in this thread someday. I just tried the bootx64.efi method and set multi to x23 but upon reboot BIOS still says x22. Because I am running Linux (lubuntu) on this machine I don't have CPU-Z to verify; maybe I'll load WinPE and verify with CPU-Z that way. HWinfo doesn't show me the multiplier in use, sadly.

Before I flash your mod, what specifically did you change? I was looking at the bit change you suggest earlier (0x390B5 0A 82 12 06 06 00 01 00), but from what I can see in the BIOS that will only unhide the menu, not unhide the hidden options in the menu. Correct? So that wouldn't expose new multipliers, I think. Take a look at the first two pics in the original post of this thread to see what I'm talking about.

Or did you change something else?

[DeathBringer]

I've changed conditions for suppressing options in Core FID&Core VID settings only.

[Eschaton]

I've changed conditions for suppressing options in Core FID&Core VID settings only.

Your mod worked almost in the way that I expected it to:

Now when I first booted I could see all the menus under "Performance" regardless of whether "Custom P-State" was enabled. I selected x23 overclock and 1.3375 overvolt, then saved and rebooted. The system successfully went to POST, and in the UEFI I got the screen below, where now I cannot choose any other option: 

   

So I need to dig around and figure out how to make the overclock actually stay applied rather than trip the failsafe settings.