WD Red 6TB - recognize, format and use full capacity - help

I have a new WD Red 6TB.
Windows 10 64bit.
Intended only for storage, not for booting. I want to create one single partition for the full capacity.

When I connect to HD via SATA cable to motherboard, the disk management utility sees the full capacity (5589.03 GB), however shows as partition only 2,048 GB. The rest stays as unallocated. I do not have the option to delete, create volume or format the unallocated part. All options are greyed out, I can only access “Properties” and “Help” (see below).

When I connect the same disk to external HD docking station (connected via USB) I can see the disk, format and use it without any problem.

When I move it back to the motherboard - again only up to 2,048 GB.

Any help would be appreciated

Hi kpa

this looks like a BIOS issue. Can you please check your BIOS if LBA, Logical Block Addressing, for internal hard drives is enabled. The first unallocated part is exactly 2048 GB aka 2 TB. This is a typical output if drives larger than 2 TB are not supported within the BIOS.

In the first unallocated part with 2048 GiB (that’s not a partition) you should be able to creat partitions. The second part is not usable. This looks like an initialization as MBR disks. The MBR partition style support max 2 TiB per drive if the logical sector size is 512 bytes. With large sectors, the limit is expanded. Only with the GPT partition style is the use of the entire space of a hard drive with more than 2 TB and 512-byte sectors possible. But older operating systems such as Windows XP still do not support GPT. For this reason, is often emulated sectors with 4096 bytes by the firmware of the USB / SATA bridge chips from external USB hard disk enclosures and docking stations. The MBR can thereby addressing hard drive with up to 16 TiB capacity and the manufactor can sold USB hard drives with more than 2 TB to customers with older computers. I think that your USB docking station makes such a 4K sector emulation.

You can check this. If the hard drive ist connected by USB with your computer, open the command prompt and type the following command:

wmic diskdrive get bytespersector,model (Exactly write like this!)

4096 = your docking station emulate a 4096 sector size.
512 = no emulation

Directly connected via SATA, have hard drives currently always a logical sector size of 512 bytes. If the former is the case, switching between internal and external connection is not possible. The emulation layer is just missing at internal connection via SATA and the sector / data assignment is no longer correct.

Thanks Madnex!

That was exactly the issue. Reformatting with GPT made the full capacity visible to Windows even without the USB docking station.

I was aware of MBR vs GPT, however I never right-clicked the box on the left, rather I was looking for options on the partition map and clearly there were (almost) none. I hope this is helpful for others having the same issue.

Much appreciated!