I have yet to install Windows on Proxmox from the scratch… I converted the existing Unraid VM to Proxmox. The below steps outline that process and I hope to update this page with instructions for a fresh install. If not, do it on Unraid and then follow the below :D. If you are attempting to install a fresh copy, use the below Proxmox Settings and then upload the iso and go from there… should be straight forward.

• OS
  • Do not use any media (we will move over out existing vdisk
  • Type: Microsoft Windows
  • Version: 11/2022/2025
• System
  • Graphic card: VMware compatible (we will add GPU passthrough later)
  • Machine: q35 9.0 (not sure why on OSX it was latest but on windows it's 9.0 (which was the latest at the time)
  • BIOS: OVMF (UEFI)
  • EFI Storage: local-lvm
  • Pre-Enroll keys: CHECKED
  • SCSI Controller: VirtIO SCSI single
  • Qemu Agent: CHECKED
  • Add TPM: CHECKED (also on local-lvm)
• Disks
  • Just create a small blank disk, we are going to erase and replace with already built disk
• CPU
  • Sockets: 1
  • Cores: 8
  • Type: host
• Memory
  • 16384
  • Ballooning Device: CHECKED
• Network
  • Bridge: vmbr0
  • Model: Intel E1000
• Confirm
  • Don't start vm after creation
  • Finish

• Wait to do the GPU until the end (or try it now, I dunno. I did the GPU after successful boot and since it was the primary GPU I did some extra stuff below)
• Datacenter → Node name → VM
• Click Hardware
  • Click Add
  • PCI Device
  • Raw Device
  • Device: Select the Device you want to add based on its address
  • All Functions: CHECKED
  • Click OK
• I did this for USB

• Erase old disk
  • Go to Datacenter → node name → windows vm
  • Click on Hardware
  • Select hard disk to remove
  • click Detach
  • click Remove
• Import new disk
  • move the new disk to a location that proxmox can see it (see adding share in the install proxmox section)
  • ssh into proxmox or open a shell (Datacenter → node name, then click >_ Shell
  • go to the folder of that new disk (cd /mnt/pve/unraid/ for example)
  • rename the image to a .raw file
  • type the import command:

    qm importdisk 202 vdisk1.raw local-lvm --format raw

    • where 202 is the vm id and local-lvm is the location.
  • after complete go to the vm → hardware and double click on the unused disk and click Add
  • go to Options → Boot Order and set the bood order to the top.
• link: https://www.youtube.com/watch?v=VlPMNgCg-ck

• Since this GPU is in the primary slot grabbed by Proxmox I did two things that i'm not sure which fixed it
  • 1: blacklist the drivers

    • echo "blacklist amdgpu" >> /etc/modprobe.d/blacklist.conf
      echo "blacklist radeon" >> /etc/modprobe.d/blacklist.conf

    • link: https://pve.proxmox.com/wiki/PCI_Passthrough
  • 2: check the PCI-Express check box below when adding the card
• Datacenter → Node name → VM
• Click Hardware
  • Click Add
  • PCI Device
  • Raw Device
  • Device: Select the Device you want to add based on its address
  • All Functions: CHECKED
  • Primary GPU: CHECKED
  • PCI-Express: CHECKED (in advanced features)
  • Click OK