A change is coming in the hard drive industry. As storage densities have increased dramatically over the years, one of the most elemental aspects of hard drive design, the logical block format size know as a sector, has remained constant.

Beginning in late 2009, accelerating in 2010 and hitting mainstream in 2011, hard drive companies are migrating away from the legacy sector size of 512 bytes to a larger, more efficient sector size of 4096 bytes, generally referred to as 4K sectors, and now referred to as the Advanced Format by IDEMA (The International Disk Drive Equipment and Materials Association).

This paper provides the context for this migration as well as pointing out the long-term benefits to customers and potential pitfalls to be avoided in the move from 512 bytes to 4K sectors.