Introduction to Common Memory model basics

Ddr=doubledatarate Double rate synchronous solid state random processor

Strictly speaking, DDR should be called Ddrsdram, people used to call DDR, some beginners also often see ddrsdram, is considered SDRAM. Ddrsdram is the abbreviation of Doubledataratesdram, which is the meaning of double speed synchronous dynamic random memory. DDR memory is developed on the basis of SDRAM memory, still follow the SDRAM production system, so for the memory vendors, only a little improvement of the equipment to create common SDRAM, can achieve the production of DDR memory, can effectively reduce costs.

What is DDR1?

Sometimes the old storage technology DDR is called DDR1, which distinguishes it from the DDR2. Although "DDR" is generally used, DDR1 has the same meaning as the DDR.

DDR1 Specifications

Ddr-200:ddr-sdram memory chips run under 100MHz ddr-266:ddr-sdram memory chips run under 133MHz ddr-333:ddr-sdram memory chips run under 166MHz ddr-400:d Dr-sdram memory chips run under 200MHZ (JEDEC DDR highest specification) Ddr-500:ddr-sdram memory chips run under 250MHz (non-JEDEC-developed DDR specs) Ddr-600:ddr-sdram memory chips 300MHz Run (non-JEDEC developed DDR specs) Ddr-700:ddr-sdram memory chips run under 350MHz (non-jedec DDR specs)

What is DDR2?

Ddr2/ddrii (DOUBLEDATARATE2) SDRAM is a new generation of memory technology standards developed by the JEDEC (Joint Commission on Electronic Equipment Engineering), the biggest difference from the previous DDR memory technology standards, although it was adopted in the rise of the clock/ The basic way of data transfer at the same time, but DDR2 memory has twice times the previous generation of DDR memory pre-read capability (that is, 4bit data read prefetching). In other words, DDR2 memory each clock can read/write data at 4 times times the speed of the external bus, and can run at 4 times times the speed of the internal control bus.

In addition, because the DDR2 standard stipulates that all DDR2 memory is in FBGA package form, and different from the current widely used TSOP/TSOP-II package form, the FBGA package can provide better electrical performance and heat dissipation property, It provides a solid foundation for the stable work of DDR2 memory and the development of future frequency. Recalling the development process of DDR, from the first generation of DDR200 to the PC through DDR266, DDR333 to today's dual-channel DDR400 technology, the development of the first generation of DDR has reached the limit of technology, it is difficult to improve the memory speed by conventional methods With the development of Intel's latest processor technology, the front-end bus requirements for memory bandwidth are increasing, with higher and more stable operating frequency of DDR2 memory will be the trend.

What is DDR3?

DDR3 is a generation of memory technology for Intel's new chips (but is currently used mainly for graphics memory), with frequencies above 800M, and DDR2 compared to the following advantages:

(1) Low power and heat consumption: Learn from the DDR2 lessons, in the control of costs based on reducing energy consumption and calorific value, making DDR3 more easily accepted by users and manufacturers.

(2) Higher working frequency: Due to lower energy consumption, DDR3 can achieve a higher frequency of work, to a certain extent to make up for the long delay of the shortcomings, but also as a video card, one of the selling points, this in the match with DDR3 memory card has been shown.

(3) Reduce the overall cost of graphics card: DDR2 video Memory particle specifications for more than 16mx32bit, with high-end graphics cards commonly used 128MB memory will need 8. and DDR3 video memory particle specifications for 32mx32bit, a single particle capacity of large, 4 can constitute 128MB video memory. In this way, the graphics card PCB area can be reduced, the cost can be effectively controlled, in addition, the reduction in the number of particles, memory power consumption will be further reduced.

(4) Good versatility: Compared to the DDR change to DDR2,DDR3 for DDR2 compatibility better. Because of the key features such as pins, encapsulation and so on, with the DDR2 display core and the public version of the design of the graphics card slightly modified to be able to use DDR3 video memory, which is very good for manufacturers to reduce costs.

At present, DDR3 has been widely used in most of the new high-end graphics cards.

Tips: We read the above for you detailed introduction of the common memory model of the basic knowledge of computer memory is not a profound understanding of it! Hope to be able to help you learn more about the basics of computer!