Running Unraid 7.0.1 on Dell T440

The T440 has a built-in VGA. I want to use the physical VGA for a dedicated display, but continue to use the virtual display as the main desktop for managing the system.

The virtual display works fine with VNC, but I'm having trouble activating the physical VGA.

As the T440 boots, the monitor attached to VGA displays the BIOS and Unraid boot process up to a shell prompt. At that time I start a browser interface.

I have this in the Windows VM configuration

Graphics Card: Virtual

VM Console Video Driver: QXL (best)

2nd Graphics Card: Matrox Electronics

2nd Graphics ROM BIOS: (empty)

I have hostdev passthrough code for the VGA controller:

IOMMU:

[102b:0536] 03:00.0 VGA compatible controller: Matrox Electronics Systems Ltd. Integrated Matrox G200eW3 Graphics Controller (rev 04)

    <hostdev mode='subsystem' type='pci' managed='yes'>

      <driver name='vfio'/>

      <source>

        <address domain='0x0000' bus='0x03' slot='0x0' function='0x0'/>

      </source>

    </hostdev>

In the Windows VM, Device Manager shows the VGA as "Microsoft Basic Display Adapter". "This Device is working properly"

I tried loading the Dell-provided drivers for the embedded Matrox video (g2w_wddm_v4_05_00_005_whql_ZPE.exe)

That actually crashed the VM and Unraid.

After restarting unraid system and the VM, Windows Settings / System / Display shows two monitors. Advanced display shows one display is QXL0001 and the other is Wired Display. Properties for Wired display are 1280x800, 8 bit.

Everything looks normal, except there is no signal on the VGA. The monitor (that showed the Unraid boot), just goes to sleep once the Windows VM starts.

I turns out that anytime I stop the Windows VM, it dirty restarts the entire UnRaid system.

I've disabled auto-run on the VM, and from Device Manager in the VM, disabled the VGA driver. I am now able to shut down the VM without taking down Unraid. But I still need to figure out why the VGA is not working properly.

Thanks to the help of @SimonF, I'm trying the approach of bind to vfio in system devices, so I removed the hostdev XML code, and checked the [102b:0536] 03:00.0 VGA compatible controller in IOMMU Group 20.

Any other suggestions to prevent full crashes of UnRaid, and enable VGA output from the Windows VM?

Edited May 26, 20251 yr by timg11

I finally got this working.

I have the passthrough set up to bind to vfio in system devices, checked the [102b:0536] 03:00.0 VGA compatible controller in IOMMU Group 20.

I disabled the VGA and restarted. This succeeded without crashing Unraid. Then I enabled the VGA and it was detected as Microsoft Basic Adapter.

That seemed to work, but only supported one mode 1200x800, which apparently the connected monitor does not support so there was no display.

I then installed the Dell Matrox drivers for the VGA instead of the Basic Adapter drivers, and re-started the VM.

Then I was able to set the resolution for the physical VGA and have an image on the monitor, along with the QXL virtual display for VNC.