Hardware Secrets
Home | Camera | Case | CE | Cooling | CPU | Input | Memory | Mobile | Motherboard | Networking | Power | Storage | Video | Other
First Look
Gabriel’s Blog
Main Menu
About Us
Awarded Products
Manufacturer Finder
RSS Feed
Test Your Skills
Subscribe today!

Home » Dictionary » Memory

A B C D E F G H I J K L M N O P Q R S T U V W X Y Z Numeric

Author: Gabriel Torres Last Updated: January 12, 2006
Category: Memory

Double Data Rate

DDR is a technique where two data are transmitted per clock cycle, instead of only one. With this technique the device achieves the double of the performance of a similar device running at the same clock rate but transferring just one data per clock cycle.

This technique is used by DDR-SDRAM memories and by the external bus of AMD CPUs (Duron, Athlon, Athlon XP, etc).

Since the device achieves a ”doubled“ performance usually the clock rate reported by the manufacturers isn’t the device’s real clock but its ”performance“ instead. For example, ”400 MHz“ DDR-SDRAM memories work at 200 MHz. Another example: Athlon XP’s external bus is said to be of 266 MHz, 333 MHz or 400 MHz while in fact it works at 133 MHz, 166 MHz and 200 MHz, respectively.

click to enlarge
Figure 1: How DDR technique works.

Related Terms:

Print Version | Send to Friend | Bookmark this Term

There are 369 terms in our database.

RSSLatest Content
GeForce GTX TITAN X Video Card Review
April 22, 2015 - 4:00 AM
A10-7800 CPU Review
April 6, 2015 - 2:50 AM
Samsung Galaxy A5 Smartphone Review
March 31, 2015 - 2:47 AM
A10-6800K vs. Core i3-4150 CPU Review
March 25, 2015 - 3:15 AM
Core i7-5960X CPU Review
February 24, 2015 - 3:00 AM
ASUS ZenFone 6 Smartphone Review
January 23, 2015 - 4:15 AM
WD My Cloud 3 TB Network HDD Review
January 19, 2015 - 4:30 AM
AMD Athlon 5150 CPU Review
January 12, 2015 - 5:30 AM

2004-15 Clube do Hardware, all rights reserved.
Advertising | Legal Information | Privacy Policy
All times are Pacific Standard Time (PST, GMT -08:00)