Dear Community,

I've got a brand new Lenovo ThinkPad X13 Yoga / i7-10510U. After a number of stress/performance tests with my other laptops, I've found it running on par with HP EliteBook x360 830 G6 / i5-8365U and a half of performance of Apple MacBook Pro 13 2020 / i5-1038NG7 -- this is a weird result and potentially i7-10510U seemed to be a superior choice but practically I'm observing a severe thermal throttling. Was wondering to undervolt but this functionality was blocked by manufacturer because of plundervolt threats. So, my motivation is to enable undervolting on X13 Yoga to tweak processor settings.

MEInfo reports that my system is Boot Guard enabled. UEFITool reports that CFG Lock sits in the yellow segment (Boot Guard protected?). Attempts to setup_var in GRUB Shell fail with "unable to write data" error.

I'm looking for an advice whether any further steps can be taken to enable undervolting.

Thanks

@Bloody Nokia Adept - Yes, due to Boot Guard you cannot edit BIOS menu, but you can change any setting hidden or visible via NVRAM Edit (with grub/setup_var or RU method)
The setup_var may be failing for you due to "Secure Boot" enabled in the BIOS, or UEFI mode etc. Disable Secure boot, and change to legacy mode if you can, then also remove any BIOS password, and disable TPM/Encryption

You cannot disable Boot Guard, and CFG lock only helps if you want to boot to MAC OSX (just in case you was not sure). The only way to disable Boot Guard is to replace the PCH with a clean one without key burned into fuse.

Here, if setup_var keeps failing you, try RU method (Adjust as needed, since what you change may not be in "Setup" varstore, which this guide is directed towards)
Go to section 2.2 and make bootable USB with RU program, then read 2.3-2.5
http://forum.notebookreview.com/threads/...-issues.812372/

From there, you can change any BIOS setting from the setup IFR

Zitat von Lost_N_BIOS im Beitrag #2

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The setup_var may be failing for you due to "Secure Boot" enabled in the BIOS, or UEFI mode etc. Disable Secure boot, and change to legacy mode if you can, then also remove any BIOS password, and disable TPM/Encryption

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Zitat von Lost_N_BIOS im Beitrag #2

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Here, if setup_var keeps failing you, try RU method (Adjust as needed, since what you change may not be in "Setup" varstore, which this guide is directed towards)Go to section 2.2 and make bootable USB with RU program, then read 2.3-2.5http://forum.notebookreview.com/threads/...-issues.812372/

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Zitat

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Changing the Lock Bit:
* If you plan on overclocking the cpu, you will need read write access to ALL regions, not just the Bios region. So before you do anything the first screen you see in RU will have some bits we need to change. If you don’t care about this, then you can skip ahead.
* Offset 00000080 and 00000090 are the locks for all the regions. (Intel Management region, Descriptor region, Bios region, etc.)
* Everything in these two lines needs to be changed to FF, but before you change them take a screenshot. These bits will need to be changed back after everything is done for security reasons. (If you don’t want to change them don’t, but any program in windows/linux could potentially write to your bios if it wanted)
* Once you have changed both lines to all FF, you can continue unlocking the bios bit.

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Do you know whether this is valid for Comet Lake (since it is still kind of one from Sky Lake architecture)? Is there any further reading on it?

Looking forward for advices! So far, no progress and BIOS is still locked.

Thanks

@Bloody Nokia Adept - That comment about line 80-90 does not apply to all BIOS, see this thread, section B, spoiler two, image one or two.
Some BIOS it's line 60 and either way not all needs FF'd for FD type #1 (line 60) or FD type #2 (line 80/90)
[Guide] Unlock Intel Flash Descriptor Read/Write Access Permissions for SPI Servicing

If you are not sure what type you have, dump FD with FPT (FPTw.exe -desc -d fd.bin) and compare to those images above, then edit as shown in those images with RU

BIOS will always remain locked here, not sure what you think you are going to accomplish by changing the BIOS lock setting, or anything in Flash descriptor either?
As I mentioned, due to boot guard, the only thing you can change in NVRAM variables, so ignore all the stuff you are looking at now, and change the settings you want to change instead

BIOS Lock you need to change may be the one in PCHSetup, it wont help you do anything here though, but for this model I'm not sure, you didn't link me to your BIOS yet?
So I don't know what varstore #5 is (please link me to BIOS download page), and the one I see on their site does not match the version info in your images at post #1
But BIOS Lock will not help you do anything, so as mentioned, ignore/forget about this and get going on your actual desired BIOS setting changes.
Sorry, I cannot view all those images like that, I am on limited internet. If there is something there you want me to see or check, put in a zip.

You may end up having to get a flash programmer (CH341A) + SOIC8 test clip.
But, even then, you will not be able to edit anything in BIOS main DXE region (ie menu changes), due to Boot Guard, but you will then not have ANY issues editing NVRAM variables directly.

If this BIOS needs PowerManagement module modified, which most systems do to run MAC OSX, along with CFG Lock settings change, then you will not be able to use this system for MAC due to boot guard stopping you from modifying modules in the main DXE Volume.
The only way you'd be able to do that would be to replace the PCH with a clean one. I will check this for you, once you link me to the BIOS.

@Lost_N_BIOS appreciate your patience and the level of support you are providing! I will need some time to digest your response. Meanwhile, here is a link to BIOS download, take to Linux version as more straightforward to unpack https://pcsupport.lenovo.com/us/en/produ...nloads/DS544145

@Bloody Nokia Adept - Thanks, I will grab windows exe and unpack, not a problem
Now that I checked BIOS, yes, BIOS Lock setting (0x17) is in PCHSetup section of NVRAM (GUID - 4570B7F1-ADE8-4943-8DC3-406472842384)

This is a multi-model/system BIOS Image, and one one of the BIOS images main DXE section is not covered by boot guard. Lets confirm which applies to your system and if menu editing is covered by boot guard or not
Please dump BIOS region via FPT using info below, just do step #1 and send me this file >>

@Lost_N_BIOS, please see a multi-part RAR archive attached. In there you'll find: BIOS dump, console output from the BIOS dump and an Intel ME report by HWInfo64.

Thanks!

@Bloody Nokia Adept - Thanks, just needed the BIOS region only No help there, bummer! What a messy BIOS, WOW!
Both images are flashed into your system too, so that's either how Lenovo does it, or someone programmed it in there wrong etc (either way, very odd!)
So, we can't tell from that, only a brick test (edit menu on purpose, to see if boot guard bricks or not) would let you know for sure, but you need flash programmer for that.

Zitat von Lost_N_BIOS im Beitrag #8

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Thanks, just needed the BIOS region only

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Zitat von Lost_N_BIOS im Beitrag #8

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Both images are flashed into your system too

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Zitat von Lost_N_BIOS im Beitrag #8

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we can't tell from that, only a brick test

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Zitat von Lost_N_BIOS im Beitrag #8

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you need flash programmer for that

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@Bloody Nokia Adept - Yes, I know this is the BIOS region My comment stands as I wrote it, that was towards Lenovo making a mess there, not you doing anything wrong

You can change BIOS settings using RU, if you can disable Secure boot and boot legacy mode, which I assume you can already do since you've been using RU
Get in there and change BIOS settings, not the ones you tried above as those are not really BIOS settings anyone would need to change except for other then when trying to flash in a mod BIOS
CFG lock you should be able to change the setting for, this is a good example of something I know you wanted to change for MAC and should be able to change easily with RU
CFG Lock, VarStoreInfo (VarOffset/VarName): 0x3E, VarStore: 0x3 >> (VarStoreId: 0x3 [B08F97FF-E6E8-4193-A997-5E9E9B0ADB32])

Flash programmer is not playing with copper and wires, it's a clip on thing with USB Dongle, don't let it scare you, people use all the time to recover from bricked BIOS
But yes, that's only something we could do, if and when you wanted, to confirm if Boot Guard would cause a brick on menu edit here or not (assume so, that is why programmer required if you wanted
But, this also applies to if you have to do CPU Power Management edit for MAC/OSX too, since one of those is in Boot Guard Covered PEI volume (and other is not)
I checked, this edit is needed for this system to run MAC OSX (MSR 0xE2 edit), x2 locations (due to dual BIOS images in there), but it's located in SiInitFsp PEI (299D6F8B-2EC9-4E40-9EC6-DDAA7EBF5FD9) in this BIOS
81E10080000033C1 Needs changed to --> 9090909090909090

So you can't run attempt to run MAC here without flash programmer, and even then it may not be possible if the one module that requires the 0xE2 edit is the boot guard covered one

Hello Lost_N_BIOS.

Since my model is quite simmilar to this model, I made an attemp to check my BIOS too.

CFG lock offset was same, ME info was same too. I came here while searching how to run mac os on my thinkpad.

I don’t know I’ve understood right : I can’t disable CFG lock without SPI-programmer, right? I could only make a dump of my bios using intel flash programmer on windows cause I found out that my chip is winbond w25q256fv which is WSON package type - can’t connect to clip.

Hi @bomdurup , yes, I've got the same perception that the clip-on flasher needed. My further experiments went nowhere and I stopped this for a while bit... Going to write a petition on Lenovo forum to enable this feature for advanced users much like Dell did on their Precision workstations with an advanced option to disable Intel ME in the configurator -- it was there on the 9th gen processor based systems but seems to gone away with latest 10th gen processors... bummer! https://www.dell.com/en-us/work/shop/wor...=configurations

@Lost_N_BIOS could you please kindly confirm?