以下是相关配置信息:

CPU: AMD Ryzen 7 8845HS
GPU: AMD Radeon 780M
Proxmox版本: 8.4.5
内核版本: 6.14.8-2~bpo12+1

/etc/default/grub

...
GRUB_CMDLINE_LINUX_DEFAULT="quiet iommu=pt initcall_blacklist=sysfb_init video=efifb:off amdgpu.dcdebugmask=0x10"
...

/etc/modules

vfio
vfio_iommu_type1
vfio_pci

/etc/modprobe.d/blacklist.conf

# block AMD driver
blacklist radeon
blacklist amdgpu

# block INTEL driver
blacklist snd_hda_intel
blacklist snd_hda_codec_hdmi
blacklist i915options

/etc/modprobe.d/kvm.conf

options kvm ignore_msrs=1

/etc/modprobe.d/vfio.conf

options vfio-pci ids=1002:1900,1002:1640
softdep amdgpu pre: vfio-pci
softdep snd_hda_intel pre: vfio-pci

/etc/pve/qemu-server/100.conf (注意适当修改)

agent: 0
balloon: 0
bios: ovmf
boot: order=ide1
cores: 8
cpu: host
efidisk0: local-zfs:vm-100-disk-0,efitype=4m,pre-enrolled-keys=1,size=1M
hostpci0: 0000:66:00.0,pcie=1,romfile=vbios_780m.bin
hostpci1: 0000:66:00.1,pcie=1
ide1: local-zfs:vm-100-disk-1,size=100G,ssd=1
machine: pc-q35-9.2+pve1
memory: 16384
meta: creation-qemu=9.2.0,ctime=XXXXXXXXXX
name: XXX
net0: e1000=XX:XX:XX:XX:XX:XX,bridge=vmbr0,firewall=1
numa: 0
ostype: win11
smbios1: uuid=XXXXXX
sockets: 1
startup: up=120
tpmstate0: local-zfs:vm-100-disk-2,size=4M,version=v2.0
vmgenid: XXXXXX

Rom来源: https://github.com/isc30/ryzen-gpu-passthrough-proxmox/blob/main/vbios_8845hs.bin

Windows内安装: https://github.com/inga-lovinde/RadeonResetBugFix

参考资料:
https://pve.proxmox.com/wiki/PCI(e)_Passthrough
https://hostbor.com/enable-amd-780m-igpu/
https://forum.proxmox.com/threads/bsod-in-windows-11-with-gpu-passthorugh-nested-virtualisation.142794/