I have a similar problem... kind of... I want to ask can someone edit/backport drivers to get Audio/Sound enable in Hyper-V Server any edition maybe universal driver for all editions? So far, audio has similar problems between WinPe and Hyper-V, so maybe the solution will be useful for both.
in order to get to this stage, a successful porting needs to be first accomplished. documentation will (hopefully) follow
has there been any progress on this? im trying to make a windows 7 VM under OVMF for experimental purposes, but even after update KB5017631 i still cant get it to boot without a CSM.
Windows 8's videoprt.sys is also different. For this to succed, Windows 8's videport drivers needs to be backported as well. Because it relies on GOP instead of the INT 10h intrerrupt and it's backwards compatible. The windows 8 basic display driver should make calls to windows 8's videport file. For it to coexist with windows 7's video port, it should be videopr8.sys to avoid creating bugs in the system. When configured this way, and when the backported drivers runs, the original videport.sys is unused by the driver.
I wonder if as many people as possible who could make these adaptations are even aware of them... This backporting is really important for the irreplaceable Windows 7, and it's really desirable that it succeeds.
The short answer is to use the Win 10 installation USB, combined with Win 7 install.esd, made easy with a cheap graphics card that uses a combined Win 7/8.1 driver. I did the following steps in a class 2 UEFI Optiplex 7050, which is easy because of its CSM (their BIOS calls it "legacy option ROMs"). Looking back on the process, this can be adapted to work in a class 3 machine. It would just require a little bit of planning and slipstreaming. Step (1) install.esd, copied from Win 7 Ult dvd, copied into Win 10 installation USB, replacing the Win 10 install file. Install Win 7 in UEFI + CSM. After step (1), the only problem with turning off CSM would be the video, so anticipating the next steps below would allow this to work on a class 3 machine. When you install Win 7 via the Win 10 USB, you need not enter your product key at the first opportunity. If you enter the product key right away, it will ignore that you're installing Ultimate. This can be fixed immediately after installation via anytime upgrade, which will work with the same product key, if you entered it up front. Step (2) installed cheap graphics card that appeared to have drivers with good support for both Win 7 & Win 8.1. Rationale is that Dell/Intel drivers for Optiplex 7050 advertised as Win 7 would not install. And Dell's mobo does not support simultaneous use of integrated and dedicated graphics. Dell's mobo requires selection of the expansion card to be made via firmware. After step (2), CSM is no longer needed for graphics. However, on this machine, turning off CSM also turns off the USB 2 drivers. I used the cheapest Nvidia graphics card, and the only drivers from their website that work are from the end of 2017. However, windows update then offers an Nvidia driver from April 2018 (which I haven't tried yet). Step (3) updated via Simplix. Now I have UEFI + Secure Boot. I'm ready to browse the internet safely, by running System Restore after every internet session. Assuming Secure Boot should protect me from BIOS malware. And System Restore should protect me from everything else. After updating via Simplix, I had partial functionality of USB 3 drivers, but there were some glitches. Also, the USB hub was not showing as functional in device manager. So I used the stand-alone USB driver pack that I believe was adopted by Simplix. This makes the USB hub functional in device manager. The Dell Optiplex 7050 has some known driver conundrums that motivated developing the solution above. The Dell/Intel GPU driver packets available on their website would not install in Win 7. This spurred me to hurry up and install the Nvidia card supported by the Win 7/8.1 drivers, which speak to the issue of this thread. Also, the Dell USB drivers do not work well, therefore providing motivation to bypass ESU with Simplix, because of its USB drivers. The original post in the following thread contains a mediafire link to the USB drivers I used : https://forums.mydigitallife.net/threads/usb-3-xhci-driver-stack-for-windows-7.81934/ One more clarification, since I was asked to describe my steps : The Win 7 Ult dvd has an install.wim. Of course, I used dism to convert this into an install.esd. I just assumed the Win 10 USB would be looking for an install.esd.
In my view about loading BasicDisplay.sys, Win8's BasicDisplay.sys calls dxgkrnl.sys in its DriverEntry with IoControlCode 0x230043, which is not implemented in Win7's dxgkrnl.sys. There are 2 ways to consider: 1. Add 0x230043 handler in Win7's dxgkrnl.sys. 2. Modify BasicDisplay.sys, call dxgkrnl.sys with IoControlCode 0x23003F, and fill some handlers that 0x23003F requires. But both ways have high uncertainty.
Given my last write-up, I thought I should provide an update about the power of the cheap graphics card with a Win 8.1 driver. The cheap expansion card is the easy way out, but this update may be useful background information for the subject of this thread. I just discovered that the Win 10 bootloader is not necessarily needed to get Win 7 to UEFI + Secure Boot without using UEFISeven. I had another of the same hardware (Opti 7050) where I previously installed Win 7, via dvd, in MBR. So I ran mbr2gpt, and then installed the cheap graphics card with the Win 8.1 drivers. After some fits and restarts, the system was able to run properly in Win 7 without CSM. I had previously failed to discover this feasibility, because on my previous attempt the graphics card's fits and restarts caused me to prematurely assume it would not work without an advanced bootloader. Today, I had less caffeine, so I let the machine do its thing until it had enough time to get the graphics working without CSM. In particular, on my first start-up without CSM under the new graphics card, the system seemed to be hung for a long time, with frozen graphics, although extensive disk activity was occurring. After a lengthy wait, the machine re-started itself, and since then it's been working just fine without CSM, and no graphics glitches. After Win 7 was working with the graphics card, and without CSM, I added the post-2019 updates via Simplix, and now it secure-boots reliably.