For some reasons, users using 3TB hard drive may find their 3TB hard only uses 2TB in Disk Management. Usually there is a 746GB around unallocated space left at the end of the hard drive. However, no matter they try to extend the 2TB partition or try to create new volume on the unallocated space, they fail, because no option in Disk Management is available.
Do you have the same experience? If you are among one of these users, at this time, the first thing you need to figure out is the reasons the lead to this issue instead of trying to find a way to make use of the total disk space.
So what causes 3TB hard drive only uses 2TB?
As a matter of fact, it is the MBR partition table that leads to 3TB hard drive showing as 2TB, and the way to fix this issue is to convert MBR to GPT. In short, MBR partition table only recognize hard drives up to 2TB; but for GPT, it is 18EB. However, if it is the system disk you want to convert, there are two things you need to pay attention to:
1. The operating system your computer is running should support GPT disk.
2. Your mainboard system uses the UEFI rather than a legacy BIOS.
Next, we will introduce the best way for you to solve 3TB hard drive only uses 2TB issue.
Usually, if Disk Management cannot help, we can turn to third-party partition manager to seek for help. And to resolve 3TB hard drive showing as 2TB, MiniTool Partition Wizard Pro is strongly recommended. Its Convert MBR to GPT feature is specially designed to convert hard drive (no matter it is system disk or data disk) from MBR to GPT without damaging data. However, users who are interested in this software need to buy a license.
See how it helps to remove 3TB hard drive only uses 2TB.
Step 1. Install and launch MiniTool Partition Wizard Pro to the main interface.
Step 2. On disk map, select the 3TB hard drive and choose Convert MBR Disk to GPT Disk from the action panel. Or you can right-click the 3TB hard drive and choose Convert MBR Disk to GPT Disk from the context menu.
Step 3.Now you can preview from the disk map that the 3TB hard drive will turn to GPT hard drive. St this time, click Apply at the top left corner to start the conversion. For the conversion of system disk, a reboot is required.
Tip: When the conversion is completed, you can create a new partition on the unallocated space or extend partition using the unallocated space.
For more methods to address 3TB hard drive only uses 2TB, read the full post How Do I Fix: 3TB Hard Drive Only Uses 2TB.