White Papers

7 512e and 4Kn Disk Formats
correction make the transition to 4K sectors well worth the effort. Managing this transition properly to
capture the long-term benefits with minimal side effects is a key focus for the hard drive industry.
4 Understanding the impacts of the 4K transition
As noted earlier, there are many aspects of modern computing systems that continue to assume that
sectors are always 512 bytes. To transition the entire industry over to the new 4K standard and expect all of
these legacy assumptions to suddenly change is not realistic. Over time, the implementation of native 4K
sectors, where both the host and hard drive exchange data in 4K blocks, will take place. Until then, Dell
and other companies will also implement the 4K sector transition in conjunction with a technique called
512-byte sector emulation.
The most critical aspect of a smooth and successful transition to 4K sectors used in Advanced Format is
performance. Whether you are a system builder, OEM, integrator, IT professional, or end user building or
configuring a computer, to ensure you have the performance you need for a successful transition, use the
operating system to align partitions on a 4Kn drive boundary.
For operating system versions that are not 4K-sector aware, use third-party software or utilities to create
hard drive partitions. To ensure the software or utilities you are using are 4K-sector aware, check with your
Dell support team.
4.1 512-byte sector emulation
The 512-byte emulation is acceptable because it does not force complex changes in legacy computing
systems. However, it carries the potential for lower performance, particularly when writing data that does
not neatly correspond to eight translated legacy sectors, as evident by the 512-byte emulation writing
process.
4.1.1 Emulated read and write processes
The 512e HDD read and write processes are illustrated below.