Stepping (version numbers)

Stepping is a letter-number designation used by Intel and AMD to identify what level of design change a microprocessor was built to. Typically, the first version of a microprocessor comes out with a stepping of A0. As design improvements occur, later versions are identified by a change in the number (for example, A3) for minor design changes and by a change to the letter and number for more extensive design changes (for example, B2). Stepping allows the consumer and servicers to identify a microprocessor s version.