Skip to main content

PC Memory: Just the Facts

DDR3 Sets Cost-and-Performance Limits

DDR3 is a relative newcomer to the memory scene, where memory modules of this type have only been available for about one year. That said, its performance ceiling continues to expand, with the JEDEC limit just met and exceeded within the past five months. Today DDR3-1600 (the JEDEC top speed) is pretty widely available, and an increasing number of vendors also offer DDR3-1800 (an overclocking variety by definition). Prototypes of DDR3-2000 have been shown at recent trade events, and products with this label are expected to be commercially available by year's end or early next year. While the JEDEC specification calls for PC3-6400/DDR3-800, we couldn't find any such memory for sale, and therefore didn't include it in the table.

LabelBus speedData rateTypical timingsRemarks
PC3-850053310667-7-7-20Usually called DDR3-1066
PC3-1066666713337-7-7-20Usually called DDR3-1333Kingston calls it PC3-11100 @ 1375
PC3-1280080016009-9-9-24Usually called DDR3-1600
PC3-1440090018009-9-9-24Usually called DDR3-1800
PC3-1600010002000TBDUsually called DDR3-2000Note yet commercially available

Table 4: Common DDR3 Memory Speeds and Nomenclature

The percentage of market penetration for DDR3, according to the memory vendors we spoke to while researching this story, still falls in the 1%-2% range, which means that DDR3 has a long way to go to match DDR sales (still in the 12%-16% range) let alone approach DDR2 sales (somewhere in the 25%-35% range in terms of current manufacturing output). Nevertheless, as the current leading-edge memory technology, this is where we expect to see the most innovation over the next year or two, particularly as motherboard chipsets and BIOS designs begin to make more room for the faster bus speeds that DDR3 demands.