UsefulAGKHelper

@reboot12 If you have seen the specs of my laptop that I sent on .txt file, the graphics card of my laptop is Intel UHD Graphics 620. If vbemp works with an Intel laptop with Intel graphics card then I should try to boot from the OS. I installed XP on virtualbox from George King's XP2ESD ISO because it's drivers may allow the OS to boot with display. And then I will copy the installation on the laptop's real HDD partition so I can boot XP from pure UEFI with FlashBoot bootmgfw.efi (laptop doesn't support legacy boot).

@reboot12 I found something bizzare when running modified XP installation from XP2ESD-based iso on pure uefi with FlashBootPro on real hardware. On serviwin I have noticed that a lot of critical drivers were enabled and disabled while XP was booting with the freezing screen. The Auto-Sysprep software from XP2ESD has managed to change the service drivers even tho there's no display. Because of XP2ESD ported generic drivers, the OS may be able to boot but even with UefiSeven/Flashboot present, xp videoprt.sys, vga.sys and vgapnp.sys still doesn't show the screen on XP on modern hardware even while these VGA emulators are used. If the problem I have is the same you have (error 50) then maybe I should try to use vbemp files by renaming vga files to see if vbemp really works on 8th gen hardware (and higher) on UEFI class 3 along with FlashBoot bootmgfw.efi.

@reboot12 Welp, I have one computer so idk how to make XP x64 run on my Coffee Lake laptop. Perhaps backporting system-type device generic drivers from Windows 7 and 8 (using NTOSKRNL EMU extender from github) that XP lacks may allow XP x64 to depend less on CSM just like windows 7 and Windows 8, perhaps maybe even allowing XP to run on new hardware with 8th core processors and beyond. If this doesn't work, then still I wouldn't be able to explain which specific drivers cause Windows 7 x64 to boot from Uefi Class 3 on modern hardware that would allow XP x64 to also work. For more information about my hardware, here are the specs (maybe from the hardware IDs, we can backport the system-type generic drivers that would allow to run XP on my hardware etc): DxDiag.txt

@reboot12 Ok I get now. Anyway, i think something should be done to 16497 winload.efi so that at least we can see the BSOD when trying to boot XP from pure UEFI (with the scope of making those errors visible so that we can know how to solve them more easily). On windows 7/vista with pure uefi, BSOD can be seen while using FlashBootPro bootmgfw.efi on pure UEFI so maybe there's some hex code in 16497 kernel that allows bootvid to display. If we can find that necessary code, then maybe bootivid and kernel dependencies from 16497 winload.efi can be removed using hex editor or disassembler to allow XP bootvid to display in order for the XP kernel to work properly on UEFI BCD.

@reboot12 Well George King has managed to implement your advice on a test iso (which you probably received already) by adding comamnds inside XP2ESD iso (inside boot.wim on setup.cmd to remove vgapnp.sys/vga.sys services (including display.inf) while using vga.sys/vgapnp.sys files are still intact and present in system32/drivers because if the drivers are not listed in services, windows wouldn't even be able to use the vga drivers even if they are present). He has tried to backport MSBDD basicdisplay.sys drivers and said that it won't even work on Windows 7, let alone Windows XP. The mistake with the code is that vga drivers will be removed even on legacy mode so there will be added an "if" command to ensure that the code works on uefi mode only.

Without VGA emulator, GOP native driver needs to be installed, vga output should be disabled from bcd and services (vga.sys/vgapnp.sys should be disabled). With VGA emulator, this isn't the case on Windows 7 because I can run windows 7 x64 from uefi class 3 as long as I have VGA emulator enabled and vga.sys/vgapnp.sys enabled (even on safe mode). I prefer to run VGA emulator with vga output enabled In order to be able to use safe mode and see a visible BSOD in case of issues.

@reboot12 If you use VGA emulator like FlashBootPro/UefiSeven, then it's no longer required to disable VGA. In fact, windows won't even display the screen if vga.sys/vgapnp.sys are disabled even if VGA emulator is used. VGA-only drivers should be disabled only when VGA emulator is absent. I can boot xp x64 from VirtualBox EFI using FlashBoot bootmgfw.efi and xp vga.sys with GUI boot disabled as long as the VGA emulator inside bootmgfw.efi is present. UefiSeven works as well, but you can also see the BSOD on FlashBootPro bootmgfw.efi (on UefiSeven, BSOD doesn't show at all on CSM-disabled UEFI).