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DRAM types

GDDR4 SDRAM (Graphics Double Data Rate, version 4) is a type of graphics card memory specified by the JEDEC Semiconductor Memory Standard. SDRAM refers to synchronous Dynamic random access memory, a term that is used to describe dynamic random access memory that has a synchronous interface SDRAM refers to synchronous Dynamic random access memory, a term that is used to describe dynamic random access memory that has a synchronous interface DDR SDRAM ( double data rate synchronous dynamic random access memory) is a class of memory Integrated circuit used in Computers It achieves nearly twice In Electronic engineering, DDR3 SDRAM or double-data-rate three Synchronous dynamic random access memory is a Random access memory Direct Rambus DRAM or DRDRAM (sometimes just called Rambus DRAM or RDRAM) is a type of synchronous dynamic RAM, designed by the Rambus XDR DRAM or extreme data rate Dynamic random access memory is a high-performance RAM interface and successor to the Rambus RDRAM it XDR2 DRAM is a type of Dynamic Random Access Memory that is offered by Rambus. V irtual C hannel R andom A ccess M emory ( VC-RAM GDDR3, Graphics Double Data Rate 3, is a graphics card-specific memory technology designed by ATI Technologies with the collaboration of JEDEC GDDR5 (Graphics Double Data Rate version 5 is a type of Graphics card memory the standards of which were set out in the GDDR5 specification by JEDEC A video card, also known as a graphics accelerator card, display adapter, or graphics card, is a hardware component whose function is to JEDEC Solid State Technology Association, formerly known as J oint E lectron D evice E ngineering C ouncil ( JEDEC) or Joint Its main competitor appears to be Rambus's XDR DRAM. Rambus Incorporated ( founded in 1990, is a provider of high-speed interface technology most notably their Rambus Dynamic RAM memory technology, which XDR DRAM or extreme data rate Dynamic random access memory is a high-performance RAM interface and successor to the Rambus RDRAM it GDDR4 is the memory successor to GDDR3. GDDR3, Graphics Double Data Rate 3, is a graphics card-specific memory technology designed by ATI Technologies with the collaboration of JEDEC It should be noted that neither is related to the JEDEC DDR3 memory standard. JEDEC Solid State Technology Association, formerly known as J oint E lectron D evice E ngineering C ouncil ( JEDEC) or Joint In Electronic engineering, DDR3 SDRAM or double-data-rate three Synchronous dynamic random access memory is a Random access memory

Contents

History

Technologies

GDDR4 SDRAM introduced DBI (Data Bus Inversion) and Multi-Preamble to reduce data transmission delay. Prefetch was increased from 4 to 8 bits. The maximum number of memory banks for GDDR4 has been increased to 8. To achieve the same bandwidth as GDDR3 SDRAM, the GDDR4 core runs at half the speed of a GDDR3 core of the same raw bandwidth. Core voltage was decreased to 1. 5 V.

On the signaling front, GDDR4 expands the chip I/O buffer to 8 bits per two cycles, allowing for greater sustained bandwidth during burst transmission, but at the expense of significantly increased CAS latency (CL), determined mainly by the double reduced count of the address/command pins and half-clocked DRAM cells, compared to GDDR3. CAS is an Abbreviation for column address strobe, or sometimes column address select, both referring to the column of the physical memory location The number of addressing pins was reduced to half that of the GDDR3 core, and were used for power and ground, which also increases latency. Another advantage of GDDR4 is power efficiency: running at 2. 4 Gbit/s, it uses 45% less power when compared to GDDR3 chips running at 2. 0 Gbit/s.

In Samsung's GDDR4 SDRAM datasheet, it was referred as 'GDDR4 SGRAM', or 'Graphics Double Data Rate version 4 Synchronous Graphics RAM'. However, the essential block write feature is not available, so it is not classified as SGRAM.

Adoption

The memory became available with ATI Technologies' Radeon X1950 XTX and Radeon HD 2900 XT and 2600 XT video cards. ATI's "R520" core (codenamed Fudo) is the foundation for a line of DirectX 9 The Graphics processing unit (GPU codenamed R600 is the foundation of the Radeon HD 2000/3000 series and the FireGL 2007 series Video GDDR4 is intended to achieve speeds as high as 1. 4 GHz (2. 8 GBit/s). In telecommunications Bit rate or Data transfer rate is the average number of Bits characters or blocks per unit time passing between equipment in a data transmission However, Samsung had aimed to increase GDDR4 to effective speeds as high as 1. The Samsung Group ( Korean:, Samsung Guerup) is South Korea 's largest company or Chaebol and the world's largest conglomerate 6 GHz (3. 2 GBit/s, at higher voltage) and was rumoured to have implemented this improvement into some of the Radeon HD 2900 XT cards.

Graphics cards incorporating GDDR4 memory are now available for purchase with a clock rate of around 1. 0 GHz to 1. 1 GHz. Samsung is quoted saying they would have 1. 6 GHz GDDR4 ready for market as early as July, 2006. NVIDIA was also rumored to have had plans of utilizing the memory on newer revisions of their current-generation GeForce 8-Series GPUs, but instead NVIDIA has used GDDR3 in all of the GeForce 8 cards. The multinational NVIDIA Corporation ( (ɪnˈvɪdiə specializes in the manufacture of graphics-processor technologies for Workstations The GeForce 8 Series is the eighth generation of NVIDIA 's GeForce graphics cards GDDR3, Graphics Double Data Rate 3, is a graphics card-specific memory technology designed by ATI Technologies with the collaboration of JEDEC

The video memory manufacturer Qimonda (formerly Infineon Memory Products division) has stated it will "skip" the development of GDDR4, and move directly to GDDR5 [6]. Qimonda AG ( (pronounced "key-MON-duh" is a Memory company split out of Infineon Technologies AG on May 1 2006 to form the second Infineon Technologies AG () was founded in April 1999 when the Semiconductor operations of parent company Siemens AG, were spun off to form a separate GDDR5 (Graphics Double Data Rate version 5 is a type of Graphics card memory the standards of which were set out in the GDDR5 specification by JEDEC

References

  1. ^ Samsung Electronics Develops Industry's First Ultra-Fast GDDR4 Graphics DRAM
  2. ^ Samsung Develops Ultra-fast Graphics Memory: A More Advanced GDDR4 at Higher Density
  3. ^ Samsung sends GDDR4 graphics memory into mass production
  4. ^ Samsung releases fastest GDDR-4 SGRAM
  5. ^ Samsung accelerates graphics memory to 2000 MHz
  6. ^ Softpedia report

External links

See also

Video memory is a term generally used in Computers to describe some form of writable memory usually RAM, dedicated to the purpose of holding the information necessary This is a list of device bandwidths: the Net bit rate (or more informally Digital bandwidth) of some computer devices employing methods of data transport is quantified
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