Bios Asus e406MAS

[rjcamatos]

Sir,
I have an Asus e406MAS, and i would like to Downgrade the BIOS, but it says roolback protection.
How can i acomplish that?

Tanks.

[rjcamatos]

Allright, i acomplish downgrade 323 version to 320 version, using a CH341APro USB Programer.
It toke some time until laptop boot again, i was doing another things, then when i look back it was alive with the 320 version.
But what i want to acomplish is to downgrade to 301 bersion (the oldest release on Asus Page).
I use the LongSoft UEFITool A59 published on GitHub to extract the raw file.
The procedure was the following:
Take out the battery, flash the rom with the programer, put it back the mainboard on the chassi, plug the Power cord without the battery, and didn't do anything else, it boot up automatically with no Power Burton press.
Now, i flash the rom with the 301 release but until now (30 minutes later) didn't boot up, i will wait a more long time to see if it will boot up.
Gone a Sleep, ler see tomorow.

[rjcamatos]

Ok, all this because the emmc memory don't shows up on bios, read next what i did ...


The settings, like the windows key i need to diff a clean bios with the extracted one with an hex editor to see if are defined there but i don't think so, but first i need to see if it is the bios version that i have that makes the internal emmc memory don't shows up on bios and on windows installer as well with the chipsets drivers loaded, i already replace the emmc memory and didn't show up.

[rjcamatos]

Ok, what i read now on a internet forum:
Since windows 8 the windows key is stored on bios, but... If is not stored there it uses the computer fingerprint to activate it throught an online channel.

[rjcamatos]

Ok, reading out some wikis, and i realize there are cpu microcode patches released on some bios to specific cpu's, this patches are loaded into cpu ram then they are used by the cpu rom microcode to load them.
Already check out my 320 bios and it have two microcode patches, and check out the 301 bios and just have one microcode patch.
Maybe, i need to power of some time the mainboard to clear out the cpu microcode ram to enable to load the 301 bios because it just have one microcode patch.
Lets see tomorow, take out the battery unplug the power cord, press power button for long long long time to enable the cpu release the last microcode patches that it load from 320 bios.
Then, try again to see if the 301 bios come alive.
Until now wait until Next day.

[rjcamatos]

Ok, in hurry, wait from 00h30 until 4h00 with the power cord connected, to see if bios 301 comes alive, and... it didn't.
Second proceduer, take out the power cord, gone a check if battery is out, and wait and wait until there are no residual power that can mantain CPU ram data.
And wait and wait.....
There is some way to reverse to 301.

[rjcamatos]

Ok,
Downgrade bios versions and results:
301 FAILL
303 FAILL
304 FAILL
311 PASS
320 PASS
323 PASS

What a [censored] why can't downgrade bellow 311?
Some One knows why?