Partitioning a USB drive allows you to divide the storage space into separate sections called partitions. This can be useful for organizing and managing the data stored on the drive, running multiple operating systems, or having separate spaces for backups or sensitive data.
There are two main partition table types used for USB drives: MBR (Master Boot Record) and GPT (GUID Partition Table). The partition table determines how many partitions can be created, the maximum partition size, and what systems can access the drive.
When partitioning a USB drive, compatibility, size limitations, number of partitions needed, bootability, security, backup/recovery, and performance are key factors to consider. This article provides an overview of MBR vs GPT partitioning and recommendations for choosing the best partition scheme for a USB drive.
MBR vs GPT
MBR stands for Master Boot Record and it’s the older partitioning scheme for hard drives. It was introduced with IBM PC DOS 2.0 in 1983. MBR supports partitions up to 2 TB in size. MBR only allows up to 4 primary partitions. If you need more than 4 partitions, you can convert one primary partition into an extended partition which can contain multiple logical drives. In MBR, the partitioning information is stored in the first sector of the drive, which is also called the boot sector (Source: https://www.howtogeek.com/193669/whats-the-difference-between-gpt-and-mbr-when-partitioning-a-drive/)
GPT stands for GUID Partition Table and it is the newer standard introduced in the Extensible Firmware Interface (EFI) as a replacement for MBR. GPT does not have the limitations of MBR. It supports disk drives up to 9.4 zettabytes and allows unlimited partitions. The partitioning information is stored in the Protective MBR and GUID Partition Table header at the start of the drive. GPT uses globally unique identifiers (GUID) to identify each partition (Source: https://www.spiceworks.com/tech/hardware/articles/mbr-vs-gpt-the-best-choice-for-your-computer/).
The main differences between MBR and GPT are:
- MBR supports up to 2 TB drives, GPT supports up to 9.4 ZB
- MBR limited to 4 primary partitions, GPT has unlimited partitions
- MBR stores partition data in boot sector, GPT stores it in header and backup
- MBR uses 32 bit LBA, GPT uses 64 bit LBA
Compatibility
MBR has broader compatibility with older operating systems like Windows XP, Windows 7, and some versions of Linux. It works with legacy BIOS systems. GPT has better compatibility with newer UEFI-based systems like Windows 8, Windows 10, Windows 11, and the latest Linux distributions. MBR is usually paired with Legacy BIOS while GPT is found on newer UEFI systems.
Windows 7 and earlier versions only support booting from an MBR disk by default. Windows 8 and later support both MBR and GPT for booting. Most Linux distributions support both MBR and GPT as well. MBR has the advantage for older legacy systems while GPT is recommended for newer UEFI-based PCs.
Size Limitations
One key difference between MBR and GPT is the maximum partition size each can support. MBR partitions have a limit of 2TB, meaning any drive partitioned with MBR is restricted to 2TB total, even if the physical drive is larger. This is due to technical limitations in the MBR partitioning scheme. MBR supports disks up to 2TB, so disks larger than 2TB must use GPT.
GPT does not have this 2TB size limitation. With GPT, partition sizes are only limited by the capacity of the drive itself. GPT supports partition sizes up to 9.4 ZB (9.4 billion TB), far exceeding the capacities of current hard drives. This makes GPT ideal for very large drives. GPT supports drives larger than 2TB.
Number of Partitions
One of the main differences between MBR and GPT is the number of partitions each supports. MBR is limited to only 4 primary partitions due to its legacy design. This can be limiting for large drives or complex setups that require more partitions. MBR does allow for extended partitions which contain logical drives, but there are still technical limitations.
In contrast, GPT supports up to 128 primary partitions on a single drive without needing to use extended partitions. This makes GPT much better suited for larger drives where more partitions are needed. With the higher limits, GPT allows for greater flexibility in partition layouts and usage scenarios.
Bootability
One key difference between MBR and GPT is bootability support across operating systems. MBR has widespread boot support while GPT has more limited compatibility.
MBR partitions can be booted by most PCs, regardless of whether the computer is running Windows, Linux, macOS, etc. This near-universal boot support makes MBR a reliable choice when creating bootable USB drives or dual-boot systems.
GPT, on the other hand, has more restrictive boot support. For example, GPT partitions cannot be natively booted on computers running legacy BIOS firmware. Instead, GPT requires more modern UEFI firmware. Thus, GPT will not boot on many older computers.
GPT boot support is also limited on macOS versions prior to Intel-based Macs. And some Linux distributions may not detect or boot GPT partitions properly without workarounds.
In summary, MBR allows booting on practically any PC while GPT has limited compatibility, especially with legacy hardware and operating systems. Those wanting maximum bootability across devices should prefer MBR over GPT.
For more information, see:
What’s the Difference Between GPT and MBR When Partitioning a Drive?
Security
When it comes to security, GPT has some advantages over MBR. One of the main differences is that GPT uses globally unique identifiers (GUIDs) to identify partitions, while MBR uses the older 32-bit logical block addressing (LBA) partition scheme.
GUIDs are much more secure than LBAs for a few reasons:
- GUIDs use 128-bit values generated randomly when the partition is created. The chances of duplicate GUIDs are extremely small, making it very unlikely an attacker could guess a partition’s GUID and access it without authorization.
- MBR’s 32-bit LBAs have a much smaller number space, making collisions more likely over time as more partitions are created. This increases the chances an unauthorized user could guess an LBA and access the partition.
- GUIDs contain a timestamp of when the partition was created. This helps prevent rollback attacks where someone restores an older MBR partition table to gain access.
In addition to GUIDs, GPT offers redundancy and error checking features that make accidental or malicious corruption of the partition table more difficult compared to MBR. GPT stores multiple copies of the partition table in different locations on the disk as backups, along with CRC32 checksums to prevent and detect tampering.
Overall, GPT’s use of GUIDs and redundancy features offer much stronger protection against unauthorized access or data loss due to disk errors or corruption. This makes GPT the better choice than MBR for security-conscious users or organizations.
Backup and Recovery
When it comes to backup and recovery, GPT has a clear advantage over MBR. GPT stores multiple partition copies for redundancy, while MBR only stores one partition table copy. https://www.stellarinfo.com/article/mbr-vs-gpt.php
The GPT header and partition table are duplicated in other locations on the drive, providing built-in backup. If the primary GPT header becomes corrupted, the backup header can be used to recover partitions. This makes recovery much easier compared to MBR, where corruption of the single MBR can mean total data loss. https://www.easeus.com/partition-master/mbr-vs-gpt.html
GPT also uses cyclic redundancy check (CRC) to detect any corruption of the partition table. Overall, the redundancy mechanisms of GPT provide much more robust protection and makes data recovery more likely to succeed if something goes wrong.
Performance
There is little difference in performance between MBR and GPT partitioning schemes (GPT vs MBR speed, MBR vs GPT in terms of speed). Both utilize the same disk I/O technologies and have similar latency and throughput. Some tests have shown GPT to be slightly faster for certain workloads, but the difference is marginal at best.
The main factors affecting storage performance are the drive interface (SATA, NVMe, etc.), controller, and internal architecture – not the partitioning method. MBR and GPT partitions exhibit nearly identical real-world speeds. Either can be used effectively for gaming, data storage, booting, or other disk operations.
In summary, performance should not be a primary factor when choosing between MBR or GPT. Both deliver fast enough speeds for practical use. The differences come down to other technical considerations around compatibility, partitions limits, and features.
Recommendations
When choosing between MBR and GPT for a USB drive, there are a few key factors to consider:
Use MBR if:
– You need compatibility with older operating systems like Windows XP or older versions of macOS (Source)
– You are creating a bootable USB drive for an older operating system or BIOS/UEFI firmware that requires MBR (Source)
Use GPT if:
– You are formatting a drive larger than 2TB, which exceeds the MBR size limit (Source)
– You need more than 4 primary partitions on the drive (Source)
– You want the extra data integrity protection offered by GPT (Source)
In general, GPT is recommended for most modern PCs, but MBR may be required for compatibility with some older systems.