Mini PC BIOS Settings for Proxmox — VT-x, VT-d, IOMMU Guide

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Getting Proxmox installed is straightforward. Getting it working correctly for VMs, LXC containers, and PCIe passthrough requires specific BIOS settings that aren’t enabled by default on most mini PCs. This guide covers the exact settings needed — and where to find them on Beelink, GMKtec, Minisforum, and GEEKOM hardware.

Before You Start

When to access BIOS:

Before installing Proxmox (recommended — configure first, install second)
After install if VMs fail or IOMMU warnings appear in Proxmox

How to enter BIOS on common mini PCs:

Brand	BIOS Key	Notes
Beelink (EQ14, SER9 PRO+)	`Delete` or `F7`	Press repeatedly during POST
GMKtec (K11)	`Delete`	Press during the GMKtec logo screen
Minisforum (UM790 Pro)	`Delete` or `F2`	May vary by model
GEEKOM (IT12, IT13)	`F2` or `Delete`	Immediately after power-on

If you miss the BIOS key window, power off and try again — the window is about 2 seconds.

The Required Settings Checklist

These settings are required for Proxmox to work correctly. Check all of them before installation.

✅ Virtualization Technology (VT-x / AMD SVM)    ENABLED
✅ VT-d (Intel) / AMD-Vi (AMD)                   ENABLED
✅ IOMMU                                          ENABLED
✅ Secure Boot                                    DISABLED
✅ Fast Boot                                      DISABLED
✅ USB Boot                                       ENABLED (for installation)
⚠️  Auto Power On                                OPTIONAL (for power outage recovery)

Setting-by-Setting Guide

1. Virtualization Technology (VT-x / AMD SVM)

What it does: Enables CPU hardware virtualization support. Without it, Proxmox cannot run KVM virtual machines.

Where to find it:

On Intel mini PCs (Beelink EQ14, GEEKOM IT12/IT13):

Advanced → CPU Configuration → Intel Virtualization Technology → Enabled

On AMD mini PCs (Beelink SER9 PRO+, GMKtec K11, Minisforum UM790 Pro):

Advanced → CPU Configuration → SVM Mode → Enabled
(SVM = Secure Virtual Machine — AMD’s name for VT-x equivalent)

Default state: Usually enabled on mid-range and high-end mini PCs. Sometimes disabled on budget N-series models. Always verify.

Proxmox check:

egrep -c '(vmx|svm)' /proc/cpuinfo
# Non-zero result = virtualization enabled
# Intel: vmx, AMD: svm

2. VT-d / AMD-Vi (IOMMU Hardware Support)

What it does: Enables hardware IOMMU, which is required for PCIe passthrough (GPU passthrough, NIC passthrough for OPNsense, USB controller passthrough).

Without VT-d/AMD-Vi, you can run VMs but cannot pass physical devices through to them. For OPNsense firewall VMs with NIC passthrough, this is non-negotiable.

Where to find it:

On Intel mini PCs:

Advanced → CPU Configuration → VT-d → Enabled
- Also check: Advanced → System Agent Configuration → VT-d → Enabled

On AMD mini PCs:

Advanced → NBIO Configuration → IOMMU → Enabled
- Or: Advanced → AMD CBS → IOMMU → Enabled

Default state: Often disabled by default, even on hardware that supports it. Must be explicitly enabled.

Proxmox check:

dmesg | grep -e DMAR -e IOMMU
# Intel: "DMAR: IOMMU enabled"
# AMD: "AMD-Vi: IOMMU enabled"

If IOMMU is not showing in this output after enabling in BIOS, you also need the kernel parameter (see Proxmox configuration below).

3. Secure Boot

What it does: Cryptographically verifies boot software. Proxmox’s bootloader is not signed for most mini PCs’ Secure Boot implementations — it won’t boot with Secure Boot enabled.

Where to find it:

Security → Secure Boot → Disabled
- Or: Boot → Secure Boot Control → Disabled

Note: Some BIOS implementations hide Secure Boot settings until you set an administrator password. If you can’t find Secure Boot settings, look for a BIOS password option first.

After disabling Secure Boot, you may also need to:

Clear Secure Boot keys: Security → Secure Boot → Key Management → Reset to Setup Mode

Re-enabling after install: You can re-enable Secure Boot after installing Proxmox if you configure MOK (Machine Owner Key). This is optional for home use — most homelab operators leave it disabled.

4. Fast Boot

What it does: Skips some hardware initialization to speed up boot time. Can prevent Proxmox’s bootloader from loading correctly.

Where to find it:

Boot → Fast Boot → Disabled
- Or: Advanced → Boot Configuration → Fast Boot → Disabled

5. C-States and Power Management

What it does: Controls CPU deep sleep states. Aggressive C-states can cause network responsiveness issues on always-on servers.

Recommendation for home servers: Leave at default (usually “Auto” or “Enabled”). Deep C-states do reduce idle power consumption. Disable only if you experience network timeout issues or VM instability attributed to CPU sleep.

If you experience problems:

Advanced → CPU Configuration → Package C State → C6 or C8 (not disabled entirely — some power saving is fine)

6. Auto Power On After Power Loss

What it does: Automatically powers on the mini PC after a power outage. Critical for a server running 24/7 — without it, a brief power outage leaves your server off until you manually press the power button.

Where to find it:

Advanced → Restore on AC Power Loss → Power On
- Or: Advanced → Power Management → AC Recovery → Always On

Set to: “Always On” or “Last State” (if you want it to remember whether it was on before the outage).

Brand-Specific BIOS Notes

Beelink EQ14 (N150)

BIOS is AMI-based with a straightforward layout. Key path:

Advanced → CPU Configuration for VT-x (Intel Virtualization Technology)
Advanced → System Agent (SA) Configuration → VT-d for IOMMU
Security → Secure Boot → Secure Boot for disabling Secure Boot

The EQ14 has VT-x enabled by default but VT-d requires manual enabling.

Beelink SER9 PRO+ (Ryzen 7 H 255)

BIOS is AMI-based. Key paths:

Advanced → CPU Configuration → SVM Mode for AMD virtualization
Advanced → NBIO Configuration → IOMMU for AMD-Vi
Some SER9 PRO+ units label IOMMU as “AMD IOMMU” under a different Advanced submenu — look through all AMD-specific menus

GMKtec K11 (Ryzen 9 8945HS)

Three TDP modes (Quiet/Balance/Performance) are in BIOS:

Advanced → AMD CBS → AMD Overclocking → Precision Boost Overdrive → set Scenario Design Power
Or use the GMKtec utility in Windows to switch modes without BIOS access

IOMMU and SVM follow the same paths as other AMD AMI BIOSes.

Minisforum UM790 Pro

More detailed BIOS than most mini PCs due to Minisforum’s engineering focus. IOMMU is under:

AMD CBS → NBIO Common Options → IOMMU → Enabled

SVM:

AMD CBS → CPU Common Options → SVM Mode → Enabled

GEEKOM IT12/IT13

AMI BIOS with a clean layout. Intel VT-d is clearly labeled:

Advanced → CPU Configuration → Intel(R) Virtualization Technology → Enabled
Advanced → System Agent (SA) Configuration → VT-d → Enabled

Both must be enabled — VT-x for basic VM support, VT-d for PCIe passthrough.

Proxmox Kernel Parameters (After BIOS Changes)

BIOS settings alone aren’t sufficient — the Linux kernel also needs parameters to activate IOMMU.

# For Intel (edit as root on the Proxmox host)
sed -i 's/GRUB_CMDLINE_LINUX_DEFAULT="quiet"/GRUB_CMDLINE_LINUX_DEFAULT="quiet intel_iommu=on iommu=pt"/' /etc/default/grub

# For AMD
sed -i 's/GRUB_CMDLINE_LINUX_DEFAULT="quiet"/GRUB_CMDLINE_LINUX_DEFAULT="quiet amd_iommu=on iommu=pt"/' /etc/default/grub

update-grub
reboot

What iommu=pt does: “Pass-through” mode improves performance by bypassing IOMMU translation for devices that don’t need DMA remapping protection. Recommended for all configurations.

Verify All Settings Are Active in Proxmox

After configuring BIOS and kernel parameters:

# Check VT-x / SVM
egrep -c '(vmx|svm)' /proc/cpuinfo
# Should return 4 or 8 (your core count)

# Check IOMMU
dmesg | grep -e DMAR -e IOMMU | head -5
# Should show IOMMU enabled message

# Check IOMMU groups exist
ls /sys/kernel/iommu_groups/ | wc -l
# Should return >0 (typically 10-30 groups)

# In Proxmox web UI
# Datacenter → Node → Shell:
pvesh get /nodes/pve/capabilities/qemu
# Look for: "kvm": 1 in the output

Quick Price Summary

Beelink EQ14 — Budget VT-x + VT-d Proxmox host
Beelink SER9 PRO+ — AMD SVM + IOMMU, 8W idle
GMKtec K11 — Full IOMMU, dual Intel NICs
Minisforum UM790 Pro — Detailed IOMMU BIOS options

Troubleshooting

Proxmox shows “No KVM support” or VMs fail to start

VT-x/SVM is not enabled. Go back to BIOS and verify the CPU virtualization setting is saved. Some BIOS interfaces require pressing F10 to save — pressing just “Save & Exit” without F10 may not persist changes.

IOMMU groups aren’t created

Both BIOS setting (VT-d/AMD-Vi) and kernel parameter must be set. Verify both. On some AMI BIOSes, the IOMMU setting is in multiple locations — ensure all are enabled.

BIOS reverts to defaults after power loss

Some mini PCs reset BIOS to factory defaults on battery drain (if the CMOS battery dies) or after power interruption. After resolving the power issue, re-enter BIOS and re-apply all settings. Set a BIOS administrator password to prevent accidental resets.

Recommended Hardware

→ Check Current Price: Beelink EQ14 on Amazon — Intel N150, VT-x + VT-d enabled, budget Proxmox host → Check Current Price: Beelink SER9 PRO+ on Amazon — Ryzen 7, AMD SVM + IOMMU, 8W idle → Check Current Price: GMKtec K11 on Amazon — Ryzen 9 8945HS, dual Intel NICs, full IOMMU support → Check Current Price: Minisforum UM790 Pro on Amazon — Ryzen 9 7940HS, detailed BIOS for IOMMU configuration

Mini PC BIOS Settings for Proxmox — VT-x, VT-d, IOMMU Guide | Mini PC Lab

Before You Start

The Required Settings Checklist

Setting-by-Setting Guide

1. Virtualization Technology (VT-x / AMD SVM)

2. VT-d / AMD-Vi (IOMMU Hardware Support)

3. Secure Boot

4. Fast Boot

5. C-States and Power Management

6. Auto Power On After Power Loss

Brand-Specific BIOS Notes

Beelink EQ14 (N150)

Beelink SER9 PRO+ (Ryzen 7 H 255)

GMKtec K11 (Ryzen 9 8945HS)

Minisforum UM790 Pro

GEEKOM IT12/IT13

Proxmox Kernel Parameters (After BIOS Changes)

Verify All Settings Are Active in Proxmox

Quick Price Summary

Troubleshooting

Proxmox shows “No KVM support” or VMs fail to start

IOMMU groups aren’t created

BIOS reverts to defaults after power loss

Recommended Hardware