Modify hidden settings by changing optimal defaults

[mfritz]

Hi!

I'm trying to change some hidden BIOS settings on a Maxsun MS-Challenger H510ITX motherboard. I'm most interested in enabling PCIE ASPM and DMI ASPM.

The most obvious solution is to unlock those options with their associated menus. However, unlocking brand new top-level menus seems quite difficult, involving a lot of trial and error steps that I do not quite understand yet.

Is it possible to modify these hidden settings by changing the "Optimal" value in AMIBCP, and then load the optimal default in the BIOS setup?

Thanks!

[mfritz]

I bit the bullet and started the challenge into BIOS modding.

It turns out that for this motherboard most UEFI variables can be modified by setup_var, except the variables in the "Setup" varstore (id: 0x1), in which any change will result in an error 0x0000001a (EFI_SECURITY_VIOLATION). To get around that I unlocked some of the hidden top level menus by swapping them with those relatively useless stock top-level menus.

In the end I managed to turn on enough power saving features on this board to make it much more suitable for 7x24 operation.

BTW one of the few advantages of these low-tier HW manufacturers is that they seem to care less about putting restrictions on their BIOSes. I was able to directly write the modded BIOS with fpt in the EFI shell without any hiccup. AFAIK most well known manufacturers these days put some sort of protection against unofficial BIOSes that would be difficult to circumvent without a hardware programmer.

[Khaled Goma]

Why are you trying to achieve this from your motherboard?

[mfritz]

Why are you trying to achieve this from your motherboard?

Mainly to lower idle power consumption. After enabling ASPM the processor is able to achieve deeper package C-states (up to C7s). Heat output of both the processor and the PCH reduce significantly.