Windows 8.1 on UEFI class 3 along with EfiGuard garbled hdmi display output

[acoul]

Official FAQ

• [X] I have checked the official FAQ.

Ventoy Version

1.0.99

What about latest release

Yes. I have tried the latest release, but the bug still exist.

Try alternative boot mode

Yes. I have tried them, but the bug still exist.

BIOS Mode

UEFI Mode

Partition Style

MBR

Disk Capacity

120GB

Disk Manufacturer

Kingston

Image file checksum (if applicable)

None

Image file download link (if applicable)

https://github.com/ventoy/Ventoy/releases/download/v1.0.99/ventoy-1.0.99-linux.tar.gz

What happened?

This is not a problem with Ventoy but rather a question as Ventoy works superbly on those two above mentioned systems (Intel N100 & Ryzen 4500U) along with others.

as I described in this EfiGuard issue, the problem appears when trying to use Ventoy along with EfiGuard

the question is here is what kind of "magic" does Ventoy deploy in combination with grubfm_multiarch.iso & how it manages to unlock & utilize the full max resolution of the display monitors under the basic display driver of the Windows 8.1, while without Ventoy, the basic display driver is unable to detect, utilize the max resolution of the display and stays either on 1024x768 or 800x600

[catherinedoyel]

what kind of "magic" does Ventoy deploy & how it manages to unlock & utilize the full max resolution

All of the Ventoy graphics comes from grub2. If you boot into grub directly you should be able to do the graphics thing? In your grub config you should be able to "chainloader"

chainloader EfiGuardDxe.efi 
chainloader bootx64.efi

the bootx64 you would put in (hd0,1)\efi\boot\bootx64.efi or whichever your Windows 8 is installed onto.

From your other post

load GrubFM iso navigate & load EfiGuardDxe.efi as device driver

Ventoy can directly run EFI binary do you get something different loading the EFI directly avoiding grubfm?

[acoul]

what kind of "magic" does Ventoy deploy & how it manages to unlock & utilize the full max resolution

All of the Ventoy graphics comes from grub2. If you boot into grub directly you should be able to do the graphics thing?

after further investigation, it's the combination of Ventoy along with loading grubfm_multiarch.iso that consistently works providing a max display resolution under the basic display driver, either on win7 or win8

loading grubfmx64.efi directly from grub2 & then the OS simply does not provide max display resolution in my case

In your grub config you should be able to "chainloader"

chainloader EfiGuardDxe.efi 
chainloader bootx64.efi

the reason for using Ventoy along with GrubFM is that these tools & OSs reside on external usb3/sata disks for testing purposes on various different hardware & platforms, thereof it helps to have a file-manager as GrubFM that can do almost anything quite easily. what I am trying to say is that this is not a static setup

Edit: I am also looking for a static method for loading win8.1 on modern systems with max display resolution under the basic display driver

Ventoy can directly run EFI binary do you get something different loading the EFI directly avoiding grubfm?

GrubFM provides the choice to load an .efi file either as an application or as a device driver

I haven't find a way to do the later with Ventoy

[acoul]

the "magic" of unlocking the max display resolution is happening on a UEFI Class 3 system under win8.1 with the basic display driver with the combination of Ventoy along with the grubfm_multiarch.iso

all other booting combinations result on a resolution of either 800x600 or 1024x768