@jmccoy555 The card I used was this one here, but it also worked with a no-name brand one I bought off newegg years ago.

Thanks, I may have to try again with an AMD card down the road!

@jmccoy555 I followed the instructions here for passing through my USB PCIe card (2 port usb 3.0 Vantec card). You have to use a PCIe USB card, trying to passthrough an onboard usb controller just doesn't work.

Did you do anything special to pass through your GPU and enable video out? Was performance close to bare metal?

Sadly not getting this to work was a show stopper for me, I had to migrate to another server 'virtual environment' which did allow me to pass both video cards through to separate VM's, with TPM support for Windows 11 VM's as a bonus. That being said, I prefer XCP-ng and the XO interface, and would switch back if I could.

@andyhhp I do have a 2nd GPU set as the primary output device in bios, and Xen uses it to display the console.. would Xen or dom0 try to use both GPU's?

@andSmv yes, unraid uses kvm, here's the xml file for reference:

<?xml version='1.0' encoding='UTF-8'?>
<domain type='kvm'>
  <name>Win10</name>
  <uuid>xxxxxxxxxxxxxx</uuid>
  <description>1TB NVME</description>
  <metadata>
    <vmtemplate xmlns="unraid" name="Windows 10" icon="windows.png" os="windows10"/>
  </metadata>
  <memory unit='KiB'>12582912</memory>
  <currentMemory unit='KiB'>12582912</currentMemory>
  <memoryBacking>
    <nosharepages/>
  </memoryBacking>
  <vcpu placement='static'>6</vcpu>
  <cputune>
    <vcpupin vcpu='0' cpuset='7'/>
    <vcpupin vcpu='1' cpuset='19'/>
    <vcpupin vcpu='2' cpuset='8'/>
    <vcpupin vcpu='3' cpuset='20'/>
    <vcpupin vcpu='4' cpuset='9'/>
    <vcpupin vcpu='5' cpuset='21'/>
  </cputune>
  <os>
    <type arch='x86_64' machine='pc-i440fx-4.2'>hvm</type>
    <loader readonly='yes' type='pflash'>/usr/share/qemu/ovmf-x64/OVMF_CODE-pure-efi-tpm.fd</loader>
    <nvram>/etc/libvirt/qemu/nvram/xxxxxuuidxxxxxx_VARS-pure-efi-tpm.fd</nvram>
  </os>
  <features>
    <acpi/>
    <apic/>
    <hyperv mode='custom'>
      <relaxed state='on'/>
      <vapic state='on'/>
      <spinlocks state='on' retries='8191'/>
      <vendor_id state='on' value='none'/>
    </hyperv>
  </features>
  <cpu mode='host-passthrough' check='none' migratable='on'>
    <topology sockets='1' dies='1' cores='3' threads='2'/>
    <cache mode='passthrough'/>
    <feature policy='require' name='topoext'/>
  </cpu>
  <clock offset='localtime'>
    <timer name='hypervclock' present='yes'/>
    <timer name='hpet' present='no'/>
  </clock>
  <on_poweroff>destroy</on_poweroff>
  <on_reboot>restart</on_reboot>
  <on_crash>restart</on_crash>
  <devices>
    <emulator>/usr/local/sbin/qemu</emulator>
    <disk type='file' device='disk'>
      <driver name='qemu' type='raw' cache='writeback'/>
      <source file='/mnt/user/domains/Windows 10/vdisk1.img'/>
      <target dev='hdc' bus='virtio'/>
      <boot order='1'/>
      <address type='pci' domain='0x0000' bus='0x00' slot='0x04' function='0x0'/>
    </disk>
    <disk type='file' device='cdrom'>
      <driver name='qemu' type='raw'/>
      <target dev='hdb' bus='ide'/>
      <readonly/>
      <address type='drive' controller='0' bus='0' target='0' unit='1'/>
    </disk>
    <controller type='usb' index='0' model='nec-xhci' ports='15'>
      <address type='pci' domain='0x0000' bus='0x00' slot='0x07' function='0x0'/>
    </controller>
    <controller type='virtio-serial' index='0'>
      <address type='pci' domain='0x0000' bus='0x00' slot='0x03' function='0x0'/>
    </controller>
    <controller type='pci' index='0' model='pci-root'/>
    <controller type='ide' index='0'>
      <address type='pci' domain='0x0000' bus='0x00' slot='0x01' function='0x1'/>
    </controller>
    <interface type='bridge'>
      <mac address='xxxxxxxmacxxxxx'/>
      <source bridge='br0'/>
      <model type='virtio-net'/>
      <address type='pci' domain='0x0000' bus='0x00' slot='0x02' function='0x0'/>
    </interface>
    <serial type='pty'>
      <target type='isa-serial' port='0'>
        <model name='isa-serial'/>
      </target>
    </serial>
    <console type='pty'>
      <target type='serial' port='0'/>
    </console>
    <channel type='unix'>
      <target type='virtio' name='org.qemu.guest_agent.0'/>
      <address type='virtio-serial' controller='0' bus='0' port='1'/>
    </channel>
    <input type='tablet' bus='usb'>
      <address type='usb' bus='0' port='1'/>
    </input>
    <input type='mouse' bus='ps2'/>
    <input type='keyboard' bus='ps2'/>
    <tpm model='tpm-tis'>
      <backend type='emulator' version='2.0' persistent_state='yes'/>
    </tpm>
    <audio id='1' type='none'/>
    <hostdev mode='subsystem' type='pci' managed='yes'>
      <driver name='vfio'/>
      <source>
        <address domain='0x0000' bus='0x07' slot='0x00' function='0x0'/>
      </source>
      <address type='pci' domain='0x0000' bus='0x00' slot='0x0a' function='0x0'/>
    </hostdev>
    <hostdev mode='subsystem' type='pci' managed='yes'>
      <driver name='vfio'/>
      <source>
        <address domain='0x0000' bus='0x0c' slot='0x00' function='0x0'/>
      </source>
      <rom file='/mnt/user/domains/Vbios/MSI.GTX1660Super.6144.191029.rom'/>
      <address type='pci' domain='0x0000' bus='0x00' slot='0x05' function='0x0' multifunction='on'/>
    </hostdev>
    <hostdev mode='subsystem' type='pci' managed='yes'>
      <driver name='vfio'/>
      <source>
        <address domain='0x0000' bus='0x0c' slot='0x00' function='0x1'/>
      </source>
      <address type='pci' domain='0x0000' bus='0x00' slot='0x05' function='0x1'/>
    </hostdev>
    <memballoon model='none'/>
  </devices>
</domain>

I've been running Unraid for a number of years, but wanted to migrate some VM's to XCP-ng to take advantage of backups, snapshots, and zfs. Looking back at my Unraid VM template settings that used this GPU for video passthrough, it was using i440fx and working great, although there were a few hoops to jump through to get it working:

The XML file of the VM needed to be edited to map the GPUs virtual video and audio devices to the same slot, and enable multifunction to get both video and audio working together.

Because its an Nvidia GPU, it also required a graphics ROM Bios to be passed through to the VM with the Nvidia header removed.

Since the nvidia driver installed correctly on the XCP-ng VM without error code 43 I assume the card was passed to the VM correctly... That's about the extent of my knowledge, thought I'd share if it helps with the hypothesis

@andSmv Ok, so if the machine model isn't Q35 a Windows VM with a modern GPU passthrough wont be able to output video to a monitor?

I tried passing the devices through to an Ubuntu 22.04 VM, installed nvidia drivers but no luck, the USB devices work but the monitor just stays off. daemon.log snippit from the Ubuntu VM:

Mar 13 14:23:55 xcp-ng squeezed: [debug||4 ||xenops] watch /data/updated <- Mon Mar 13 15:23:55 2023
Mar 13 14:24:01 xcp-ng squeezed[1338]: [195.83] watch /data/updated <- 1
Mar 13 14:24:01 xcp-ng squeezed: [debug||4 ||xenops] watch /data/updated <- 1
Mar 13 14:24:01 xcp-ng ovs-ofctl: ovs|00001|ofp_util|WARN|Negative value -1 is not a valid port number.
Mar 13 14:24:01 xcp-ng ovs-vsctl: ovs|00001|vsctl|INFO|Called as ovs-vsctl --timeout=30 -- --if-exists del-port tap5.0
Mar 13 14:24:02 xcp-ng tapback[8597]: frontend.c:216 768 front-end supports persistent grants but we don't
Mar 13 14:24:02 xcp-ng tapdisk[8587]: received 'sring connect' message (uuid = 5)
Mar 13 14:24:02 xcp-ng tapdisk[8587]: connecting VBD 5 domid=5, devid=768, pool (null), evt 33, poll duration 1000, poll idle threshold 50
Mar 13 14:24:02 xcp-ng tapdisk[8587]: ring 0x1b38810 connected
Mar 13 14:24:02 xcp-ng tapdisk[8587]: sending 'sring connect rsp' message (uuid = 5)
Mar 13 14:24:03 xcp-ng qemu-dm-5[8842]: [00:08.0] Write-back to unknown field 0xc4 (partially) inhibited (0x00000000)
Mar 13 14:24:03 xcp-ng qemu-dm-5[8842]: [00:08.0] If the device doesn't work, try enabling permissive mode
Mar 13 14:24:03 xcp-ng qemu-dm-5[8842]: [00:08.0] (unsafe) and if it helps report the problem to xen-devel
Mar 13 14:24:03 xcp-ng qemu-dm-5[8842]: [00:07.0] Write-back to unknown field 0x44 (partially) inhibited (0x00)
Mar 13 14:24:03 xcp-ng qemu-dm-5[8842]: [00:07.0] If the device doesn't work, try enabling permissive mode
Mar 13 14:24:03 xcp-ng qemu-dm-5[8842]: [00:07.0] (unsafe) and if it helps report the problem to xen-devel
Mar 13 14:24:05 xcp-ng squeezed[1338]: [200.14] domid 5 just started a guest agent (but has no balloon driver); calibrating memory-offset = 0 KiB
Mar 13 14:24:05 xcp-ng squeezed: [debug||3 ||xenops] domid 5 just started a guest agent (but has no balloon driver); calibrating memory-offset = 0 KiB
Mar 13 14:24:05 xcp-ng squeezed[1338]: [200.14] watch /memory/memory-offset <- 0
Mar 13 14:24:05 xcp-ng squeezed: [debug||4 ||xenops] watch /memory/memory-offset <- 0
Mar 13 14:24:05 xcp-ng squeezed[1338]: [200.14] Xenctrl.domain_setmaxmem domid=5 max=6292480 (was=6347776)
Mar 13 14:24:05 xcp-ng squeezed: [debug||3 ||xenops] Xenctrl.domain_setmaxmem domid=5 max=6292480 (was=6347776)
Mar 13 14:24:11 xcp-ng squeezed[1338]: [206.39] watch /data/updated <- Mon Mar 13 14:24:11 2023
Mar 13 14:24:11 xcp-ng squeezed: [debug||4 ||xenops] watch /data/updated <- Mon Mar 13 14:24:11 2023

@andSmv sure thing, I can't post the whole output as it's too long to post, but heres the output pertaining to the GPU and USB card

0b:00.0 VGA compatible controller: NVIDIA Corporation TU116 [GeForce GTX 1660 SUPER] (rev a1) (prog-if 00 [VGA controller])
        Subsystem: Micro-Star International Co., Ltd. [MSI] Device c75a
        Control: I/O+ Mem+ BusMaster+ SpecCycle- MemWINV- VGASnoop- ParErr- Stepping- SERR- FastB2B- DisINTx-
        Status: Cap+ 66MHz- UDF- FastB2B- ParErr- DEVSEL=fast >TAbort- <TAbort- <MAbort- >SERR- <PERR- INTx-
        Latency: 0, Cache Line Size: 64 bytes
        Interrupt: pin A routed to IRQ 54
        Region 0: Memory at fb000000 (32-bit, non-prefetchable) [size=16M]
        Region 1: Memory at b0000000 (64-bit, prefetchable) [size=256M]
        Region 3: Memory at c0000000 (64-bit, prefetchable) [size=32M]
        Region 5: I/O ports at f000 [size=128]
        [virtual] Expansion ROM at fc000000 [disabled] [size=512K]
        Capabilities: [60] Power Management version 3
                Flags: PMEClk- DSI- D1- D2- AuxCurrent=375mA PME(D0+,D1-,D2-,D3hot+,D3cold+)
                Status: D0 NoSoftRst+ PME-Enable- DSel=0 DScale=0 PME-
        Capabilities: [68] MSI: Enable- Count=1/1 Maskable- 64bit+
                Address: 0000000000000000  Data: 0000
        Capabilities: [78] Express (v2) Legacy Endpoint, MSI 00
                DevCap: MaxPayload 256 bytes, PhantFunc 0, Latency L0s unlimited, L1 <64us
                        ExtTag+ AttnBtn- AttnInd- PwrInd- RBE+ FLReset+
                DevCtl: Report errors: Correctable- Non-Fatal- Fatal- Unsupported-
                        RlxdOrd+ ExtTag+ PhantFunc- AuxPwr- NoSnoop- FLReset-
                        MaxPayload 128 bytes, MaxReadReq 512 bytes
                DevSta: CorrErr- UncorrErr- FatalErr- UnsuppReq- AuxPwr+ TransPend-
                LnkCap: Port #0, Speed 8GT/s, Width x16, ASPM L0s L1, Exit Latency L0s <1us, L1 <4us
                        ClockPM+ Surprise- LLActRep- BwNot- ASPMOptComp+
                LnkCtl: ASPM Disabled; RCB 64 bytes Disabled- CommClk+
                        ExtSynch- ClockPM+ AutWidDis- BWInt- AutBWInt-
                LnkSta: Speed 8GT/s, Width x16, TrErr- Train- SlotClk+ DLActive- BWMgmt- ABWMgmt-
                DevCap2: Completion Timeout: Range AB, TimeoutDis+, LTR+, OBFF Via message
                DevCtl2: Completion Timeout: 50us to 50ms, TimeoutDis-, LTR-, OBFF Disabled
                LnkCtl2: Target Link Speed: 8GT/s, EnterCompliance- SpeedDis-
                         Transmit Margin: Normal Operating Range, EnterModifiedCompliance- ComplianceSOS-
                         Compliance De-emphasis: -6dB
                LnkSta2: Current De-emphasis Level: -3.5dB, EqualizationComplete+, EqualizationPhase1+
                         EqualizationPhase2+, EqualizationPhase3+, LinkEqualizationRequest-
        Capabilities: [100 v1] Virtual Channel
                Caps:   LPEVC=0 RefClk=100ns PATEntryBits=1
                Arb:    Fixed- WRR32- WRR64- WRR128-
                Ctrl:   ArbSelect=Fixed
                Status: InProgress-
                VC0:    Caps:   PATOffset=00 MaxTimeSlots=1 RejSnoopTrans-
                        Arb:    Fixed- WRR32- WRR64- WRR128- TWRR128- WRR256-
                        Ctrl:   Enable+ ID=0 ArbSelect=Fixed TC/VC=01
                        Status: NegoPending- InProgress-
        Capabilities: [250 v1] Latency Tolerance Reporting
                Max snoop latency: 0ns
                Max no snoop latency: 0ns
        Capabilities: [258 v1] L1 PM Substates
                L1SubCap: PCI-PM_L1.2+ PCI-PM_L1.1+ ASPM_L1.2+ ASPM_L1.1+ L1_PM_Substates+
                          PortCommonModeRestoreTime=255us PortTPowerOnTime=10us
        Capabilities: [128 v1] Power Budgeting <?>
        Capabilities: [420 v2] Advanced Error Reporting
                UESta:  DLP- SDES- TLP- FCP- CmpltTO- CmpltAbrt- UnxCmplt- RxOF- MalfTLP- ECRC- UnsupReq- ACSViol-
                UEMsk:  DLP- SDES- TLP- FCP- CmpltTO- CmpltAbrt- UnxCmplt- RxOF- MalfTLP- ECRC- UnsupReq- ACSViol-
                UESvrt: DLP+ SDES+ TLP- FCP+ CmpltTO- CmpltAbrt- UnxCmplt- RxOF+ MalfTLP+ ECRC- UnsupReq- ACSViol-
                CESta:  RxErr- BadTLP- BadDLLP- Rollover- Timeout- NonFatalErr-
                CEMsk:  RxErr- BadTLP- BadDLLP- Rollover- Timeout- NonFatalErr+
                AERCap: First Error Pointer: 00, GenCap- CGenEn- ChkCap- ChkEn-
        Capabilities: [600 v1] Vendor Specific Information: ID=0001 Rev=1 Len=024 <?>
        Capabilities: [900 v1] #19
        Capabilities: [bb0 v1] #15
        Kernel driver in use: pciback

0b:00.1 Audio device: NVIDIA Corporation TU116 High Definition Audio Controller (rev a1)
        Subsystem: Micro-Star International Co., Ltd. [MSI] Device c75a
        Control: I/O- Mem+ BusMaster+ SpecCycle- MemWINV- VGASnoop- ParErr- Stepping- SERR- FastB2B- DisINTx-
        Status: Cap+ 66MHz- UDF- FastB2B- ParErr- DEVSEL=fast >TAbort- <TAbort- <MAbort- >SERR- <PERR- INTx-
        Latency: 0, Cache Line Size: 64 bytes
        Interrupt: pin B routed to IRQ 55
        Region 0: Memory at fc080000 (32-bit, non-prefetchable) [size=16K]
        Capabilities: [60] Power Management version 3
                Flags: PMEClk- DSI- D1- D2- AuxCurrent=0mA PME(D0-,D1-,D2-,D3hot-,D3cold-)
                Status: D0 NoSoftRst+ PME-Enable- DSel=0 DScale=0 PME-
        Capabilities: [68] MSI: Enable- Count=1/1 Maskable- 64bit+
                Address: 0000000000000000  Data: 0000
        Capabilities: [78] Express (v2) Endpoint, MSI 00
                DevCap: MaxPayload 256 bytes, PhantFunc 0, Latency L0s unlimited, L1 <64us
                        ExtTag+ AttnBtn- AttnInd- PwrInd- RBE+ FLReset- SlotPowerLimit 75.000W
                DevCtl: Report errors: Correctable- Non-Fatal- Fatal- Unsupported-
                        RlxdOrd+ ExtTag+ PhantFunc- AuxPwr- NoSnoop+
                        MaxPayload 128 bytes, MaxReadReq 512 bytes
                DevSta: CorrErr- UncorrErr- FatalErr- UnsuppReq- AuxPwr- TransPend-
                LnkCap: Port #0, Speed 8GT/s, Width x16, ASPM L0s L1, Exit Latency L0s <1us, L1 <4us
                        ClockPM+ Surprise- LLActRep- BwNot- ASPMOptComp+
                LnkCtl: ASPM L0s L1 Enabled; RCB 64 bytes Disabled- CommClk+
                        ExtSynch- ClockPM+ AutWidDis- BWInt- AutBWInt-
                LnkSta: Speed 8GT/s, Width x16, TrErr- Train- SlotClk+ DLActive- BWMgmt- ABWMgmt-
                DevCap2: Completion Timeout: Range AB, TimeoutDis+, LTR+, OBFF Via message
                DevCtl2: Completion Timeout: 50us to 50ms, TimeoutDis-, LTR-, OBFF Disabled
                LnkSta2: Current De-emphasis Level: -3.5dB, EqualizationComplete-, EqualizationPhase1-
                         EqualizationPhase2-, EqualizationPhase3-, LinkEqualizationRequest-
        Capabilities: [100 v2] Advanced Error Reporting
                UESta:  DLP- SDES- TLP- FCP- CmpltTO- CmpltAbrt- UnxCmplt- RxOF- MalfTLP- ECRC- UnsupReq- ACSViol-
                UEMsk:  DLP- SDES- TLP- FCP- CmpltTO- CmpltAbrt- UnxCmplt- RxOF- MalfTLP- ECRC- UnsupReq- ACSViol-
                UESvrt: DLP+ SDES+ TLP- FCP+ CmpltTO- CmpltAbrt- UnxCmplt- RxOF+ MalfTLP+ ECRC- UnsupReq- ACSViol-
                CESta:  RxErr- BadTLP- BadDLLP- Rollover- Timeout- NonFatalErr-
                CEMsk:  RxErr- BadTLP- BadDLLP- Rollover- Timeout- NonFatalErr+
                AERCap: First Error Pointer: 00, GenCap- CGenEn- ChkCap- ChkEn-
        Kernel driver in use: pciback

0b:00.2 USB controller: NVIDIA Corporation TU116 USB 3.1 Host Controller (rev a1) (prog-if 30 [XHCI])
        Subsystem: Micro-Star International Co., Ltd. [MSI] Device c75a
        Control: I/O- Mem+ BusMaster+ SpecCycle- MemWINV- VGASnoop- ParErr- Stepping- SERR- FastB2B- DisINTx-
        Status: Cap+ 66MHz- UDF- FastB2B- ParErr- DEVSEL=fast >TAbort- <TAbort- <MAbort- >SERR- <PERR- INTx-
        Latency: 0, Cache Line Size: 64 bytes
        Interrupt: pin C routed to IRQ 52
        Region 0: Memory at c2000000 (64-bit, prefetchable) [size=256K]
        Region 3: Memory at c2040000 (64-bit, prefetchable) [size=64K]
        Capabilities: [68] MSI: Enable- Count=1/1 Maskable- 64bit+
                Address: 0000000000000000  Data: 0000
        Capabilities: [78] Express (v2) Endpoint, MSI 00
                DevCap: MaxPayload 128 bytes, PhantFunc 0, Latency L0s unlimited, L1 <64us
                        ExtTag+ AttnBtn- AttnInd- PwrInd- RBE+ FLReset- SlotPowerLimit 75.000W
                DevCtl: Report errors: Correctable- Non-Fatal- Fatal- Unsupported-
                        RlxdOrd+ ExtTag+ PhantFunc- AuxPwr- NoSnoop+
                        MaxPayload 128 bytes, MaxReadReq 512 bytes
                DevSta: CorrErr- UncorrErr- FatalErr- UnsuppReq- AuxPwr+ TransPend-
                LnkCap: Port #0, Speed 8GT/s, Width x16, ASPM L0s L1, Exit Latency L0s <1us, L1 <4us
                        ClockPM+ Surprise- LLActRep- BwNot- ASPMOptComp+
                LnkCtl: ASPM Disabled; RCB 64 bytes Disabled- CommClk+
                        ExtSynch- ClockPM- AutWidDis- BWInt- AutBWInt-
                LnkSta: Speed 8GT/s, Width x16, TrErr- Train- SlotClk+ DLActive- BWMgmt- ABWMgmt-
                DevCap2: Completion Timeout: Range AB, TimeoutDis+, LTR+, OBFF Via message
                DevCtl2: Completion Timeout: 50us to 50ms, TimeoutDis-, LTR-, OBFF Disabled
                LnkSta2: Current De-emphasis Level: -3.5dB, EqualizationComplete-, EqualizationPhase1-
                         EqualizationPhase2-, EqualizationPhase3-, LinkEqualizationRequest-
        Capabilities: [b4] Power Management version 3
                Flags: PMEClk- DSI- D1- D2- AuxCurrent=55mA PME(D0+,D1-,D2-,D3hot+,D3cold+)
                Status: D0 NoSoftRst+ PME-Enable- DSel=0 DScale=0 PME-
        Capabilities: [100 v2] Advanced Error Reporting
                UESta:  DLP- SDES- TLP- FCP- CmpltTO- CmpltAbrt- UnxCmplt- RxOF- MalfTLP- ECRC- UnsupReq- ACSViol-
                UEMsk:  DLP- SDES- TLP- FCP- CmpltTO- CmpltAbrt- UnxCmplt- RxOF- MalfTLP- ECRC- UnsupReq- ACSViol-
                UESvrt: DLP+ SDES+ TLP- FCP+ CmpltTO- CmpltAbrt- UnxCmplt- RxOF+ MalfTLP+ ECRC- UnsupReq- ACSViol-
                CESta:  RxErr- BadTLP- BadDLLP- Rollover- Timeout- NonFatalErr-
                CEMsk:  RxErr- BadTLP- BadDLLP- Rollover- Timeout- NonFatalErr+
                AERCap: First Error Pointer: 00, GenCap- CGenEn- ChkCap- ChkEn-
        Kernel driver in use: pciback
        Kernel modules: xhci_pci

0b:00.3 Serial bus controller [0c80]: NVIDIA Corporation TU116 USB Type-C UCSI Controller (rev a1)
        Subsystem: Micro-Star International Co., Ltd. [MSI] Device c75a
        Control: I/O- Mem+ BusMaster+ SpecCycle- MemWINV- VGASnoop- ParErr- Stepping- SERR- FastB2B- DisINTx-
        Status: Cap+ 66MHz- UDF- FastB2B- ParErr- DEVSEL=fast >TAbort- <TAbort- <MAbort- >SERR- <PERR- INTx-
        Latency: 0, Cache Line Size: 64 bytes
        Interrupt: pin D routed to IRQ 53
        Region 0: Memory at fc084000 (32-bit, non-prefetchable) [size=4K]
        Capabilities: [68] MSI: Enable- Count=1/1 Maskable- 64bit+
                Address: 0000000000000000  Data: 0000
        Capabilities: [78] Express (v2) Endpoint, MSI 00
                DevCap: MaxPayload 128 bytes, PhantFunc 0, Latency L0s unlimited, L1 <64us
                        ExtTag+ AttnBtn- AttnInd- PwrInd- RBE+ FLReset- SlotPowerLimit 75.000W
                DevCtl: Report errors: Correctable- Non-Fatal- Fatal- Unsupported-
                        RlxdOrd+ ExtTag+ PhantFunc- AuxPwr- NoSnoop+
                        MaxPayload 128 bytes, MaxReadReq 512 bytes
                DevSta: CorrErr- UncorrErr- FatalErr- UnsuppReq- AuxPwr+ TransPend-
                LnkCap: Port #0, Speed 8GT/s, Width x16, ASPM L0s L1, Exit Latency L0s <1us, L1 <4us
                        ClockPM+ Surprise- LLActRep- BwNot- ASPMOptComp+
                LnkCtl: ASPM Disabled; RCB 64 bytes Disabled- CommClk+
                        ExtSynch- ClockPM- AutWidDis- BWInt- AutBWInt-
                LnkSta: Speed 8GT/s, Width x16, TrErr- Train- SlotClk+ DLActive- BWMgmt- ABWMgmt-
                DevCap2: Completion Timeout: Range AB, TimeoutDis+, LTR+, OBFF Via message
                DevCtl2: Completion Timeout: 50us to 50ms, TimeoutDis-, LTR-, OBFF Disabled
                LnkSta2: Current De-emphasis Level: -3.5dB, EqualizationComplete-, EqualizationPhase1-
                         EqualizationPhase2-, EqualizationPhase3-, LinkEqualizationRequest-
        Capabilities: [b4] Power Management version 3
                Flags: PMEClk- DSI- D1- D2- AuxCurrent=55mA PME(D0+,D1-,D2-,D3hot+,D3cold+)
                Status: D0 NoSoftRst+ PME-Enable- DSel=0 DScale=0 PME-
        Capabilities: [100 v2] Advanced Error Reporting
                UESta:  DLP- SDES- TLP- FCP- CmpltTO- CmpltAbrt- UnxCmplt- RxOF- MalfTLP- ECRC- UnsupReq- ACSViol-
                UEMsk:  DLP- SDES- TLP- FCP- CmpltTO- CmpltAbrt- UnxCmplt- RxOF- MalfTLP- ECRC- UnsupReq- ACSViol-
                UESvrt: DLP+ SDES+ TLP- FCP+ CmpltTO- CmpltAbrt- UnxCmplt- RxOF+ MalfTLP+ ECRC- UnsupReq- ACSViol-
                CESta:  RxErr- BadTLP- BadDLLP- Rollover- Timeout- NonFatalErr-
                CEMsk:  RxErr- BadTLP- BadDLLP- Rollover- Timeout- NonFatalErr+
                AERCap: First Error Pointer: 00, GenCap- CGenEn- ChkCap- ChkEn-
        Kernel driver in use: pciback

06:00.0 USB controller: NEC Corporation uPD720200 USB 3.0 Host Controller (rev 04) (prog-if 30 [XHCI])
        Subsystem: Samsung Electronics Co Ltd Device c0a5
        Control: I/O- Mem+ BusMaster+ SpecCycle- MemWINV- VGASnoop- ParErr- Stepping- SERR- FastB2B- DisINTx+
        Status: Cap+ 66MHz- UDF- FastB2B- ParErr- DEVSEL=fast >TAbort- <TAbort- <MAbort- >SERR- <PERR- INTx-
        Latency: 0, Cache Line Size: 64 bytes
        Interrupt: pin A routed to IRQ 29
        Region 0: Memory at fa700000 (64-bit, non-prefetchable) [size=8K]
        Capabilities: [50] Power Management version 3
                Flags: PMEClk- DSI- D1- D2- AuxCurrent=0mA PME(D0+,D1-,D2-,D3hot+,D3cold-)
                Status: D0 NoSoftRst+ PME-Enable- DSel=0 DScale=0 PME-
        Capabilities: [70] MSI: Enable- Count=1/8 Maskable- 64bit+
                Address: 0000000000000000  Data: 0000
        Capabilities: [90] MSI-X: Enable- Count=8 Masked-
                Vector table: BAR=0 offset=00001000
                PBA: BAR=0 offset=00001080
        Capabilities: [a0] Express (v2) Endpoint, MSI 00
                DevCap: MaxPayload 128 bytes, PhantFunc 0, Latency L0s unlimited, L1 unlimited
                        ExtTag- AttnBtn- AttnInd- PwrInd- RBE+ FLReset- SlotPowerLimit 0.000W
                DevCtl: Report errors: Correctable- Non-Fatal- Fatal- Unsupported-
                        RlxdOrd- ExtTag- PhantFunc- AuxPwr- NoSnoop+
                        MaxPayload 128 bytes, MaxReadReq 512 bytes
                DevSta: CorrErr- UncorrErr- FatalErr- UnsuppReq- AuxPwr- TransPend-
                LnkCap: Port #0, Speed 5GT/s, Width x1, ASPM L0s L1, Exit Latency L0s <4us, L1 unlimited
                        ClockPM+ Surprise- LLActRep- BwNot- ASPMOptComp-
                LnkCtl: ASPM Disabled; RCB 64 bytes Disabled- CommClk+
                        ExtSynch- ClockPM+ AutWidDis- BWInt- AutBWInt-
                LnkSta: Speed 5GT/s, Width x1, TrErr- Train- SlotClk+ DLActive- BWMgmt- ABWMgmt-
                DevCap2: Completion Timeout: Not Supported, TimeoutDis+, LTR+, OBFF Not Supported
                DevCtl2: Completion Timeout: 50us to 50ms, TimeoutDis-, LTR+, OBFF Disabled
                LnkCtl2: Target Link Speed: 5GT/s, EnterCompliance- SpeedDis-
                         Transmit Margin: Normal Operating Range, EnterModifiedCompliance- ComplianceSOS-
                         Compliance De-emphasis: -6dB
                LnkSta2: Current De-emphasis Level: -3.5dB, EqualizationComplete-, EqualizationPhase1-
                         EqualizationPhase2-, EqualizationPhase3-, LinkEqualizationRequest-
        Capabilities: [100 v1] Advanced Error Reporting
                UESta:  DLP- SDES- TLP- FCP- CmpltTO- CmpltAbrt- UnxCmplt- RxOF- MalfTLP- ECRC- UnsupReq- ACSViol-
                UEMsk:  DLP- SDES- TLP- FCP- CmpltTO- CmpltAbrt- UnxCmplt- RxOF- MalfTLP- ECRC- UnsupReq- ACSViol-
                UESvrt: DLP+ SDES+ TLP- FCP+ CmpltTO- CmpltAbrt- UnxCmplt- RxOF+ MalfTLP+ ECRC- UnsupReq- ACSViol-
                CESta:  RxErr- BadTLP- BadDLLP- Rollover- Timeout- NonFatalErr-
                CEMsk:  RxErr- BadTLP- BadDLLP- Rollover- Timeout- NonFatalErr+
                AERCap: First Error Pointer: 00, GenCap- CGenEn- ChkCap- ChkEn-
        Capabilities: [140 v1] Device Serial Number ff-ff-ff-ff-ff-ff-ff-ff
        Capabilities: [150 v1] Latency Tolerance Reporting
                Max snoop latency: 0ns
                Max no snoop latency: 0ns
        Kernel driver in use: pciback
        Kernel modules: xhci_pci

@olivierlambert Looking at the daemon.log, when the VM is started up there's a few lines pertaining to the video card:

Mar 13 11:13:23 xcp-ng qemu-dm-5[9111]: 9111@1678724003.619415:xen_platform_log xen platform: xen|ModuleAdd: FFFFF8022F400000 - FFFFF8022F4E0FFF [dxgmms2.sys]
Mar 13 11:13:23 xcp-ng qemu-dm-5[9111]: [00:0b.0] Write-back to unknown field 0x0c (partially) inhibited (0x00000000)
Mar 13 11:13:23 xcp-ng qemu-dm-5[9111]: [00:0b.0] If the device doesn't work, try enabling permissive mode
Mar 13 11:13:23 xcp-ng qemu-dm-5[9111]: [00:0b.0] (unsafe) and if it helps report the problem to xen-devel
Mar 13 11:13:24 xcp-ng qemu-dm-5[9111]: 9111@1678724004.067025:xen_platform_log xen platform: xen|ModuleAdd: FFFFF8022F510000 - FFFFF8022F552FFF [hidclass.sys]

I removed the devices from the vm using vm-param-remove, rebooted the machine, confirmed the devices were in the pci assignable list, then ran the following 4 commands:

echo 0000:0b:00.0 > /sys/bus/pci/drivers/pciback/permissive
echo 0000:0b:00.1 > /sys/bus/pci/drivers/pciback/permissive
echo 0000:0b:00.2 > /sys/bus/pci/drivers/pciback/permissive
echo 0000:0b:00.3 > /sys/bus/pci/drivers/pciback/permissive

I re-assigned the PCI devices to the VM and re-booted, no change to the video out issue and the daemon.log still produces the same lines as above.

I've also hit a few BSOD's stating Video TDR failure, with nvlddmkm.sys failing.

Is this the proper way to set permissive mode?

Hi, I've been working on this for a while and I can say I'm officially stuck and out of ideas. My goal is to have a Windows 10 VM running on XCP-ng with Xen Orchestra, with an Nvidia GTX 1660 Super and a PCIe X1 USB controller card passed through to the VM. The VM will act as my daily driver, with Keyboard, mouse, etc connected to the USB card and a monitor connected via DP to the 1660.

The computer has two video Cards, the GTX 1660 Super and a GTX 1030. The Bios is set to use the GTX 1030 as the primary display, IOMMU is enabled, and local apic mode is set to x2apic. So far, I've done the following:

Fresh install of xcp-ng 8.2.1
Ran yum update, and yum upgrade
Created new Win10 VM, ran all updates and shut down VM.
Under Advanced tab, enabled Manage Citrix PV drivers via Windows Update and installed Citrix drivers and restarted.
Found the PCI devices by running lspci (06:00.0 for the USB card, 0b:00.0/.1/.2/.3 for the GPU)
Ran xen-pciback.hide on the above items
After reboot, confirmed they were listed under xl pci-assignable-list
Assigned them to the VM using xe vm-param-set
Started VM and installed latest Nvidia drivers

The issue I'm running into is the system is not usable at all. The monitor keeps cutting in and out, allowing about 5-10 seconds of desktop time then about 20 seconds of black screen. When the desktop is visible, animations such as clicking on the start menu are very slow and staggered. I was able to download and install the Nvidia drivers and restart, but this didn't solve/improve the issue. Device manager shows the GPU installed and functioning normally. When looking at display devices, it lists two devices, my monitor and the console on XO. Disabling the console monitor didn't affect performance. On the plus side my keyboard and mouse seem to be functioning flawlessly.

Any idea what would be causing these display issues? Any help or a nudge in the right direction would be greatly appreciated!

System config:
Ryzen 5900X
Gigabyte X570 UD Mobo
32GB Ram
Nvidia GTX 1660 Super
USB Controller Card
Nvidia GTX 1030
USB Controller Card
Chelsio 10GbE Network Card