> ## Documentation Index
> Fetch the complete documentation index at: https://docs.edisglobal.com/llms.txt
> Use this file to discover all available pages before exploring further.

# UEFI vs BIOS and vTPM in EDIS Global VPS

> Differences between BIOS and UEFI boot modes on an EDIS Global VPS, plus when to enable vTPM for Windows 11, BitLocker, and other modern Windows features.

## 🆕 UEFI, BIOS & vtpm overview

EDIS Global VPS supports both **BIOS (legacy boot)** and **UEFI (modern boot)**, as well as **vTPM (software-based Trusted Platform Module)**.

These options are primarily relevant for **operating system compatibility**, especially for modern systems like Windows 11.

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## 🧭 BIOS vs UEFI

### 🟢 BIOS (Default)

* Legacy boot mode
* Maximum compatibility
* Works with all supported operating systems
* Recommended for most Linux installations

👉 **Default setting on all VPS**

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### 🔵 UEFI

* Modern boot standard
* Required for newer operating systems
* Supports advanced features like Secure Boot

Required for:

* Windows 11
* Windows Server 2025

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## 🔐 What is vTPM?

vTPM (Virtual Trusted Platform Module) is a **software emulation of a TPM chip**.

It is required for:

* Windows 11 installation
* Certain OS security features (disk encryption, secure boot chains)

### Options

* **None (Default)** → TPM disabled
* **Software TPM** → TPM enabled

👉 Only enable vTPM if your operating system requires it

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## ⚙️ Default Configuration

To ensure maximum compatibility:

* **Boot Mode:** BIOS
* **TPM:** Disabled

These defaults are suitable for the majority of use cases.

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## 🤖 Auto-Installer Behavior

When using EDIS Global **Auto-Installers**:

* BIOS / UEFI is **automatically selected**
* TPM is **enabled or disabled as required**

👉 Manual settings are **ignored** to ensure successful installation

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## 🧩 When manual configuration matters

Manual BIOS / UEFI / TPM settings are relevant when:

### ✔️ Custom Cloud-Init images

* You can:
  * Use current VPS settings, or
  * Override boot mode and TPM during deployment

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### ✔️ Custom ISO / uploaded images

* VPS will use the **System Configuration settings**
* If needed:
  1. Change Boot Mode / TPM
  2. **Power-cycle the VPS**
  3. Boot your image

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## ⚠️ Important Considerations

### OS Compatibility

* A significant number of operating systems are **not UEFI-compatible**
* Switching from BIOS → UEFI on an existing installation will usually result in:
  * ❌ Boot failure

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### Changing boot mode

* Boot mode must match how the OS was installed
* Changing it later requires:
  * Reinstallation, or
  * Advanced manual recovery

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### TPM Usage

* Not required for Linux in most cases
* Only enable when explicitly needed
* Adds complexity without benefit if unused

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## 🧾 Quick Recommendations

* Use **BIOS + no TPM** for:
  * Linux servers
  * General-purpose workloads
* Use **UEFI + TPM** only for:
  * Windows 11 / modern Windows deployments

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## 🧭 Summary

| Feature   | Default  | When to Change           |
| --------- | -------- | ------------------------ |
| Boot Mode | BIOS     | Only if OS requires UEFI |
| TPM       | Disabled | Only if OS requires TPM  |

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If you are unsure which configuration to use, the **Auto-Installer will always choose the correct setup automatically**.