Go to Kingston.com Homepage UNITED STATES  
Kingston New Technology


JEDEC Specifications and Naming Conventions

The specifications for DDR memory modules are developed and approved by JEDEC. JEDEC is the semiconductor standardization body of the Electronic Industries Alliance (EIA). About 300 member companies representing every segment of the industry actively participate to develop standards to meet the industry needs. Kingston is a long-time member of JEDEC and is active on the JEDEC Board of Directors as well as a number of memory technology committees.

JEDEC has provided specifications for PC1600, PC2100, PC2700, and PC3200 which are now widely available. Development work on faster DDR2 and DDR3 memory technologies is on-going.

In the case of 400MHz PC3200 or faster DDR technologies, DRAM chipset, and motherboard manufacturers have defined specifications for select applications in the gaming and enthusiast market.

JEDEC 200/266/333/400MHz DDR Specifications Summary

  • 184 pin DIMM, ECC or non-ECC
  • 200 pin SO-DIMM, ECC or non-ECC
  • 172 pin Micro-DIMM, non-ECC
  • 2.5 Volts
  • SSTL-2 I/O Interface
  • CAS Latencies: 2, 2.5
  • Serial Presence Detect (SPD) Support
  • Support for Memory Chip Stacking
  • Compatible with Kingston's EPOC™ technology for Registered modules
DDR naming convention recommended by JEDEC:

Memory chips are referred to by their native speed:

For example, 200 MHz DDR SDRAM memory chips are called DDR200 chips, 266 MHz DDR SDRAM memory chips are called DDR266 chips, and 333 MHz DDR SDRAM memory chips are called DDR333 chips.
DDR modules are named after their peak bandwidth, which is the maximum amount of data that can be delivered per second:
A 200 MHz DDR DIMM is called a PC1600 DIMM, and a 266 MHz DDR DIMM is called a PC2100 DIMM. A 333 MHz DDR DIMM is called a PC2700 DIMM. A 400MHz DDR DIMM is called PC3200.

See the DDR Memory Bandwidth section for details on how bandwidth is computed.

© 2008 Kingston Technology Corporation - All Rights Reserved