Hard Disks are based on 512 byte sectors and access to it is addressed based on this unit. However, these days, hard disk manufacturers have started manufacturing hard disks having a sector size of 4096 bytes. These are called Advanced Format Disks, also called 4K Sector Drives or 512e drives.
Advanced Format Disks
The coming years will see the data storage industry move towards using this physical format of hard disk drives from 512-byte sectors to 4,096-byte sectors, also known as 4K or 4KB sectors.
Why? Changing this sector format convention to a larger physical sectors allows more efficient use of the storage surface area especially for larger It also allows for enhanced data protection and correction algorithms, increased data reliability and greater format efficiencies resulting in a better user experiences. Check out this slide show to learn more about it.
For more information, resources and links on Advanced Format Disks, head over to IDEMA.org. IDEMA (International Disk Drive Equipment and Materials Association) is the storage industry trade organization.
Now, when a 512 byte write is directed to such advanced format disks, it will require work and resource, which comes at the cost of performance and reliability. To avoid this additional work, applications must be updated to natively support writes that are based on the 4 KB sector granularity.
Native 512e drives are currently not supported with Windows. However, 512e drives are supported with recent versions of Windows, provided that you follow the guidance in KB2510009.
Microsoft has released an update to improve the compatibility of Windows 7 and Windows Server 2008 R2 with Advanced Format Disks is available and you can get it at KB982018. This hotfix is only applicable to Advanced Format disks which report themselves as having a 4 KB physical sector size, and which emulate a logical addressing interface of 512 bytes.