# Hardware requirements by Windows version: 11 26H2, LTSC and Server

> One matrix for TPM, Secure Boot, CPU support, RAM and storage across Windows 11 26H2, LTSC 2024, Server 2025 and Server 2022 — and what each rule protects.

**Tested on**

- Build: 26300.9457 / 26100.33650
- Edition: Pro (26H2) / Server
- Architecture: x64
- Evidence: E1
- Verified: 2026-10-29

## The short answer

Windows 11 is the strict one: **UEFI + Secure Boot capable + TPM 2.0 + a support-listed CPU**. Windows Server does not require TPM or Secure Boot to install, but VBS/Credential Guard and BitLocker work better with them.

That asymmetry explains most "Server installs fine, Windows 11 refuses" surprises.

## The matrix

| Requirement | Windows 11 26H2 | Windows 11 LTSC 2024 | Server 2025 | Server 2022 |
|---|---|---|---|---|
| Firmware | UEFI | UEFI | UEFI or legacy | UEFI or legacy |
| Secure Boot | Capable, enabled by policy | Capable | Not required | Not required |
| TPM | **2.0 required** | **2.0 required** | Not required | Not required |
| CPU | Support list | Support list | Support list | Support list |
| RAM | 4GB minimum | 4GB minimum | 2GB (Core) / 4GB | 2GB / 4GB |
| Storage | 64GB | 64GB | 32GB | 32GB |
| Virtualization | Optional (VBS) | Optional | Optional (Hyper-V) | Optional |
| DirectX | 12 / WDDM 2.0 | 12 / WDDM 2.0 | Not applicable | Not applicable |

The CPU support list is the part people skip. A CPU can be fast and still unsupported: Microsoft publishes the requirement that the processor be on the supported list for the Windows release, and OEMs only ship firmware for supported combinations. See [CPU support checks](https://winbook.fyi/en/hardware/cpu/support-microcode/).

## What each rule actually protects

- **TPM 2.0** stores BitLocker keys, backs Windows Hello and Credential Guard, and measures boot state. Without it, Windows 11's device encryption cannot work.
- **Secure Boot** ensures only signed boot components run. It is also what makes some anti-cheat and anti-tamper features possible.
- **UEFI** (not CSM) is required for Secure Boot and for features like memory integrity.
- **Supported CPU** reduces the chance that firmware/microcode stops receiving fixes.

> **Caution: fTPM vs discrete TPM**
>
> A firmware TPM (fTPM/PTT) satisfies Windows 11 and is free — it is a switch in firmware setup. A discrete TPM is preferable on machines that hibernate/encrypt heavily and on some motherboards with fTPM stutter issues, but it is not required. Both count as TPM 2.0 when correctly enabled.

## Server is not "Windows 11 without TPM"

Server drops the consumer requirements, but adds its own:

- **Drivers**: server NICs/storage controllers must have Server-certified drivers. Consumer drivers often refuse to install.
- **Roles**: Hyper-V requires SLAT; Storage Spaces Direct requires specific hardware.
- **Editions**: Standard covers two OSEs, Datacenter unlimited — a licensing constraint that changes hardware planning more than any spec.

## Check a machine before you install

```powershell
# firmware mode, Secure Boot, TPM
Confirm-SecureBootUEFI
Get-Tpm | Select-Object TpmPresent,TpmReady,ManufacturerIdTxt
Get-CimInstance Win32_ComputerSystem | Select-Object Manufacturer,Model
(Get-CimInstance Win32_ComputerSystem).BootupState

# CPU identity and virtualization exposure
Get-CimInstance Win32_Processor | Select-Object Name,NumberOfCores,NumberOfLogicalProcessors,VirtualizationFirmwareEnabled
```

`VirtualizationFirmwareEnabled : False` on a CPU that supports it means the firmware switch is off — an easy fix that unlocks Hyper-V/VBS later.

## Upgrade paths that avoid a reinstall

- Windows 11 Pro → Enterprise: edition upgrade with a key, no reinstall.
- Server evaluation → licensed edition: needs a valid key; plan storage and roles first.
- Windows 10 → 11: the hardware checks above decide it; there is no supported bypass for TPM/Secure Boot.

## Related

- [Install Windows 11 cleanly](https://winbook.fyi/en/windows/install/clean/)
- [Preflight checks before install](https://winbook.fyi/en/windows/install/preflight/)
- [Server editions and licensing](https://winbook.fyi/en/server/start/editions-licensing/)

## Lab boundary

E1. Requirements are quoted from Microsoft's published documentation. The lab machines (26H2 and LTSC 2024 VMs) satisfy them through OVMF + vTPM.

## Sources

- [Microsoft Learn — Windows 11 requirements](https://learn.microsoft.com/en-us/windows/whats-new/windows-11-requirements)
- [Microsoft Learn — Windows Server hardware requirements](https://learn.microsoft.com/en-us/windows-server/get-started/hardware-requirements)
- [Microsoft Learn — Windows processor requirements](https://learn.microsoft.com/en-us/windows-hardware/design/minimum/windows-processor-requirements)
- [Microsoft Learn — TPM fundamentals](https://learn.microsoft.com/en-us/windows/security/hardware-security/tpm/tpm-fundamentals)

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Source: https://winbook.fyi/en/hardware/buy/os-hardware-matrix/