Browse Definitions:
Definition

serial presence detect (SPD)

Contributor(s): Kris Faulkner

When a computer is booted (started), serial presence detect (SPD) is information stored in an electrically erasable programmable read-only memory (EEPROM) chip on a synchronous dynamic random access memory (SDRAM) memory module that tells the basic input/output system (BIOS) the module's size, data width, speed, and voltage. 

The BIOS uses this information to configure the memory properly for maximum reliability and performance. If a memory module does not have SPD, the BIOS assumes the memory module's information. With some memory, this does not cause problems. But SDRAM memory has to have SPD or the computer may not boot at all. If it does boot, the assumed information may cause fatal exception errors

Before SPD, memory chips were identified with parallel presence detect (PPD). PPD used a separate pin for each bit of information,which meant that only the speed and density of the memory module could be stored because of the limited space for pins. The EEPROM chip on an SPD memory module only requires two pins so more information can be stored.

This was last updated in July 2015

Continue Reading About serial presence detect (SPD)

Start the conversation

Send me notifications when other members comment.

By submitting you agree to receive email from TechTarget and its partners. If you reside outside of the United States, you consent to having your personal data transferred to and processed in the United States. Privacy

Please create a username to comment.

-ADS BY GOOGLE

File Extensions and File Formats

Powered by:

SearchCompliance

  • internal audit (IA)

    An internal audit (IA) is an organizational initiative to monitor and analyze its own business operations in order to determine ...

  • pure risk (absolute risk)

    Pure risk, also called absolute risk, is a category of threat that is beyond human control and has only one possible outcome if ...

  • risk assessment

    Risk assessment is the identification of hazards that could negatively impact an organization's ability to conduct business.

SearchSecurity

  • principle of least privilege (POLP)

    The principle of least privilege (POLP), an important concept in computer security, is the practice of limiting access rights for...

  • identity management (ID management)

    Identity management (ID management) is the organizational process for identifying, authenticating and authorizing individuals or ...

  • zero-day (computer)

    A zero-day vulnerability, also known as a computer zero day, is a flaw in software, hardware or firmware that is unknown to the ...

SearchHealthIT

SearchDisasterRecovery

  • business continuity and disaster recovery (BCDR)

    Business continuity and disaster recovery (BCDR) are closely related practices that describe an organization's preparation for ...

  • business continuity plan (BCP)

    A business continuity plan (BCP) is a document that consists of the critical information an organization needs to continue ...

  • call tree

    A call tree -- sometimes referred to as a phone tree -- is a telecommunications chain for notifying specific individuals of an ...

SearchStorage

SearchSolidStateStorage

  • hybrid hard disk drive (HDD)

    A hybrid hard disk drive is an electromechanical spinning hard disk that contains some amount of NAND Flash memory.

Close