Take the 2-minute tour ×
Super User is a question and answer site for computer enthusiasts and power users. It's 100% free, no registration required.

I have a 1 TB external USB hard drive that is GUID partitioned with a 100MB FAT32 EFI partition.

The thing is that its a 1 terabyte drive. From what I'm aware, the limit is at 2 tebibytes (TiB). Therefore, the GPT isn't necessary, and MBR could be used instead.

TL;DR: What would happen if I delete the EFI partition and reformat as MBR partition table on an external drive not booted from?

share|improve this question
    
"The thing is that its a 1.5 terabyte drive. From what I'm aware, the limit is at 2 terabytes. So LBA with GPT isn't necessary." Why are you asking if you already know the answer? –  Breakthrough Dec 21 '12 at 15:58
    

1 Answer 1

up vote 5 down vote accepted

What would happen if I delete the EFI partition and reformat as MBR partition table on an external drive not booted from?

Nothing. It would still just work.


But you do seem to mix EFI and GPT, so let me give a longer answer:

MBR is a very old way of partitioning drives on a PC. It only allowed for four primary partitions, or, with a workaround, for 3 primary and several more "extended" partitions. It also tops out at 2.0 TiB (232 512 byte sectors), or 2.20 TB.

The GUID Partition Table (aka GPT), on the other hand, is a more modern way of dividing a drive into partitions. It allows for drives larger than 2 TiB, and it allows for way more partitions (up to 128 specifically).

There is nothing which stops you from selecting either method on a small enough drive. Both methods are valid. Any modern computer should be able to handle both of them, either via the BIOS or EUFI.


There are three catches here though:

  • If you use ancient software (e.g. Windows XP, which came out before the GPT scheme was created), then it will not understand GPT.
  • If you use a old BIOS, then it may not understand GPT. (A modern BIOS should understand it, though there are quite a few which fail).
  • If you partition a drive larger then 2.0 TiB with the MBR scheme, you will not be able to access anything past the 2 TiB mark. Your 1 TB drive, however, is small enough that this does not matter.
share|improve this answer

Your Answer

 
discard

By posting your answer, you agree to the privacy policy and terms of service.

Not the answer you're looking for? Browse other questions tagged or ask your own question.