DDR-II (or DDR2) memory is the new high-performance RAM architecture deigned to overcome the challenges of current DDR DRAM technology. It is the next- generation solution of main memory offering greater bandwidth and density in a smaller package at reduced power consumption and is supported by dozens of major computer vendors.

DDR2 memory chips are already being used on high-end graphic cards but this is a different standard than the one we that will be used on memory modules.  DDR2 memory modules will be similar in design but will NOT be backwards compatible with DDR memory slots*.  They will also continue to support important DDR features such as dual-channel memory support.

Normal DDR limitations at higher frequencies:

• Signal integrity
• Power Consumption

DDR2 Addresses these challenges by:

• Operating voltage is reduced from 2.5V to 1.8V
• Reduced core operating frequency
• Core frequency = 1/2 the I/O frequency 

Special New Features:

• 4-bit pre-fetch
• On-die termination
• Off-chip driver calibration

*In addition to the electrical and signaling changes DDR2 modules will have a slightly different physical interconnect than DDR modules.  The edge-connector "notch" will be in a lightly different position to prevent accidentally plugging in the incorrect module type. See pictures below.