Hey Guys I am running into a hell of an issue with my new build. I originally had a 3070 5600X build and had no issue with any of this. This build has completely stumped me. I am assuming its unfixable but I am hoping someone will know better. Here is a detailed outline of all I've tried. The end result is I can only boot the VM a 2nd time after a full shutdown IF I disable the GPU audio.

TL;DR

RTX 5090 passthrough on Unraid is stable only when the NVIDIA HD Audio function (01:00.1) is removed.
The audio device fails FLR on VM shutdown, dead-bridges the PCIe slot, and triggers Error 127 on restart.

With PCIe power management disabled, vfio_pci.disable_idle_d3=1, GPU-only passthrough, and a VBIOS ROM supplied, the VM can start/stop/restart indefinitely.

Trade-off: no HDMI/DP audio. Looking to confirm whether this is an expected limitation on RTX 50-series GPUs under Unraid, or if a supported audio-safe approach exists.

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System

• Host: Unraid (current stable)

• GPU: NVIDIA RTX 5090 (GB202)

• VM: Windows 11

• Hypervisor: KVM / QEMU

• Passthrough: VFIO

• Motherboard: ASRock X870E Taichi

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Objective

Achieve repeatable, stable GPU passthrough of an RTX 5090 to a Windows 11 VM without requiring a host reboot between VM restarts.

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Observed Failure

• VM boots correctly on first start

• Any VM restart after shutdown fails

• GPU remains unusable until a full host power cycle

Error

internal error: Unknown PCI header type '127' for device '0000:01:00.0'

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Root Cause

The failure is reproducible and isolated to:

• 01:00.1 – NVIDIA HD Audio Controller

• The device fails FLR on VM shutdown

• This leaves the PCIe slot in a dead state

This matches the known NVIDIA reset bug, now observed on GB202.

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Platform / Firmware Configuration

The following motherboard and firmware settings are applied and verified.

Component	Setting Category	Setting	Required Value / Status	Purpose
Motherboard	–	ASRock X870E Taichi	–	Platform in use
CPU / Virtualization	AMD CPU Features	SVM Mode	Enabled	Enables CPU virtualization
IOMMU	AMD Chipset Features	AMD IOMMU	Enabled	Enables interrupt and memory remapping
Power Management	ACPI / Power	Global C-States	Disabled	Prevents deep CPU sleep states
Boot	Boot Features	Fast Boot	Disabled	Forces full hardware initialisation

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Final Working Configuration

Kernel Parameters

pcie_acs_override=downstream,multifunction
pcie_aspm=off
pcie_port_pm=off
vfio_pci.disable_idle_d3=1

Notes:

• vfio_pci.disable_idle_d3=1 is required in this configuration

• Prevents the GPU from entering PCIe D3cold/D3hot states

• Without it, the PCIe link can fail to recover reliably

• This does not resolve the reset bug on its own

• Stability still requires removal of the audio function

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VBIOS ROM

A VBIOS ROM file is supplied:

<rom file='/mnt/user/isos/rtx5090.rom'/>

Used for consistent GPU initialisation only.
Unrelated to the FLR/reset failure.

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Audio Function

• 01:00.1 (NVIDIA HD Audio Controller) permanently removed

• Only 01:00.0 (GPU) passed through

This resolves:

• Error 127

• PCIe dead-bridge condition

• Requirement for host power cycles

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Current State

Working

• GPU passthrough is stable

• VM can start/stop/restart indefinitely

• No PCIe errors

Not Available

• HDMI / DisplayPort audio (expected due to removal of audio function)

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Question

At this point the system is stable.

Looking to confirm whether:

• This is expected behaviour for RTX 50-series GPUs under Unraid

• There is any supported way to retain GPU audio without reintroducing reset failures

If the answer is simply “not currently possible”, that’s fine — just looking to confirm the limitation.

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Summary

• RTX 5090 passthrough is reliable and repeatable

• Stability requires:

  • PCIe power management disabled

  • vfio_pci.disable_idle_d3=1

  • NVIDIA audio function removed

• Result is a working VM with no GPU-provided audio

Any insight from others running GB202 would be useful.

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I had no choice but to use a headset or a usb speaker in order to have audio.

I did exactly the same thing USB audio but obviously that sucks overall. I am glad to hear it's not just me! I'm sorry we are in this boat together. Happy new year to you

@PUNGGOKERS Did you find any solution?

Sorry for nobby question but where to put the kernel parameters you mentioned like "vfio_pci.disable_idle_d3=1"?

I am having stability issues with my RTX 5080 too.

Thanks,

No solution unfortunately just disable audio. I'm afraid I'm not around to check for sure but a quick Google should bring up the path

On 1/8/2026 at 3:02 PM, taygun said:

@PUNGGOKERS Did you find any solution?

Sorry for nobby question but where to put the kernel parameters you mentioned like "vfio_pci.disable_idle_d3=1"?

I am having stability issues with my RTX 5080 too.

Thanks,

You add the kernel parameters in syslinux configuration: