DDR3 Memory
DDR3 continues the trend, doubling the minimum read or write unit to 8 consecutive words. This allows another doubling of bandwidth and external bus speed without having to change the speed of internal operations, just the width.
DDR3 memory chips are being made commercially, and computer systems are available that use them as of the second half of 2007, with expected significant usage in 2008. Initial speeds were 400 and 533 MHz, which would be described as DDR3-800 and DDR3-1066, but 667 and 800 MHz (DDR3-1333 and DDR3-1600) are now common and speeds up to DDR3-1800 are available for a price.
The primary benefit of DDR3 is the ability to transfer I/O data at eight times the speed of the memory cells it contains, thus enabling faster bus speeds and higher peak throughput than earlier memory technologies. However, there is no corresponding reduction in latency, which is therefore proportionally higher. In addition, the DDR3 standard allows for chip capacities of 512 megabits to 8 gigabits, effectively enabling a maximum memory module size of 16 gigabytes.
DDR3-800 100 MHz 10 ns 400 MHz 800 Million PC3-6400 6400 MB/s
DDR3-1066 133 MHz 7.5 ns 533 MHz 1066 Million PC3-8500 8533 MB/s
DDR3-1333 166 MHz 6 ns 667 MHz 1333 Million PC3-10600 10667 MB/s[1]
DDR3-1600 200 MHz 5 ns 800 MHz 1600 Million PC3-12800 12800 MB/s
Speed
DDR3 SDRAM SDRAM DIMMs - DIMMs based on Double Data Rate 3(DDR3) DRAM have data and strobe frequencies at double the rate of the clock. This is achieved by clocking on both the rising and falling edge of the data strobes. The power consumption and voltage of DDR3 is lower than DDR2 of the same speed.
* PC3-6400 = 800 MHz data & strobe / 400 MHz clock for address and control
* PC3-8500 = 1066 MHz data & strobe / 533 MHz clock for address and control
* PC3-10600 = 1333 MHz data & strobe / 667 MHz clock for address and control
* PC3-12800 = 1600 MHz data & strobe / 800 MHz clock for address and control
Number of Pins
Compare DDR2 and DDR3 Memory (note notch)
DDR3 DIMMs have 240 pins, the same number as DDR2, and are the same size, but are electrically incompatible and have a different key notch location.
Installation
Compatibility
Are not backwards compatible-wrongly inserting a DDR3 module into a DDR2 socket can damage the DIMM and/or the motherboard
Available Memory Sizes
