Why and How to Convert System Boot Disk to GPT Standard?


Windows XP, Windows Vista, Windows 7, Windows 8...What’s next? Microsoft always brings us various kinds of surprises. With the upgrade of software, the hardware are also should be replaced. Before Windows XP, most motherboard don’t support UEFI. But Windows operating system after Windows XP started to support GPT disk. What’s the relationship between them?

The two items are often confusing. Now I’ll explain in detail:

  • UEFI stands for Unified Extensible Firmware Interface, an upgrade of EFI. It is a specification that defines a software interface between platform firmware and the operating system.
  • UEFI supports hard disks with either MBR or GPT system. MBR, namely master boot record, is a old style but still used by many vendors. GPT is a newer standard.
  • Systems that support UEFI require that boot partition must reside on a GPT disk. Other hard disks can be either MBR or GPT.


Converting MBR to GPT, why? One reason is as I noted above. The second reason is that if you want to expand a partition more than 2TB (MBR only supports a maximum partition size of 2TB). GPT supports theoretically unlimited partitions. By contrast, MBR only supports 4 primary partitions per hard drive.

Above are main two reasons. So if you think GPT is useful to you, converting to it without hesitate please.

With only a few steps, you can convert MBR to GPT successfully. Provided there is a tool to do so.

There really have a one - AOMEI Partition Assistant Professional Edition. Download it first, install and run.

Select disk and click convert
(Step 1: Right-click on system disk and select "Convert to GPT Disk)


Click “OK” in the pop-up window
(Step 2: Click “OK” in the pop-up window)


Click “Yes” after reading the note
(Step 3: Click “Yes” after reading the note)


Apply and proceed
(Step 4&Step 5: Apply and proceed)

It’s really simple, only a few clicks! It keep the system and data safe at the same time. AOMEI Partition Assistant is known for professional and efficient.

If you are interested, please experience the amazing functions “Windows to go creator”, “migrate OS to SSD”, and “rebuild MBR” provided by AOMEI Partition Assistant. Other practical function such as resizing partition, copying partition, splitting partition, merging partition, etc. I hope you try and enjoy it yourself. Our website have lots of article tutorials and videos which will help you a lot.