1- Enable Virtualization in BIOS

Enter BIOS and enable:

• VT-x / SVM
• VT-d / IOMMU
• Above 4G decoding (important for GPUs)

Save and reboot.

---

2- Enable IOMMU in Proxmox

Edit GRUB:

nano /etc/default/grub

For Intel:

GRUB_CMDLINE_LINUX_DEFAULT="quiet intel_iommu=on iommu=pt"

For AMD:

GRUB_CMDLINE_LINUX_DEFAULT="quiet amd_iommu=on iommu=pt"

Update grub:

update-grub

Reboot.