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Does anyone here have any knowledge in laptop BIOS modifications? More specifically for an ASUS TUF laptop. I need a fix for a major issue my laptop has that ASUS themselves will not support.

@Violet i know this much: if it has intel boot guard or the amd equivalent, nothing can be done

@Violet that said, if you're trying to change a setting, it might be possible to do it pre-ExitBootServices...

@Rairii I bring this up because there already is an existing mod for the FX505DU so I'm assuming it can't be impossible to do this for the FX505DT 239239.blogspot.com/2019/09/me

@Violet i mean i guess i could take a look at the firmware image when i get time if i remember

@Violet i took a look at the firmware image. according to Setup IFR, the AMD fTPM switch is the byte at offset 0x2A of {EC87D643-EBA4-4BB5-A1E5-3F3E36B20DA9}!Setup variable.

0=enabled if no other TPM is present, 1=disabled, 2=force use of external TPM on SPI bus

(default is 0)

you should be able to use something like RU.efi to edit it

@Rairii omg thank you so much, I will have a look into using RU.efi and hopefully that will work. I'm not really familiar with these kinda tools since I've never needed to use them before so hopefully I don't end up bricking my laptop in the process.

@Violet you might want to be sure your os device has bitlocker disabled or not used first, windows likes to enable it automatically

@Rairii is it possible I could have a basic explanation on how to use this tool? I think I've found what I'm looking for but I can't see the full GUID because it gets cut off the edge of the UI

@Rairii just want to be 100% sure I know what I'm doing, I change this value to 01 then save -> register file

right?

@Violet that looks correct to me

one guide i see says ctrl+w saves though?

@Violet EFI_SECURITY_VIOLATION
let me just reverse SetVariable implementation and see if there's a way around that

@Violet ok so

as far as I can tell, the variable starts out "unlocked" (you can write to it)

then when actually booting something it locks it in software

and unlocks it again when the bootloader exits

the thing is, it's done by an event on a protocol GUID being installed

an EFI application can do this

that EFI application, zipped and base64'd, is as follows:

gist.github.com/Wack0/5241c471

reboot, run this (it should say it worked) then try RU.efi again

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