In spite of memory module makers’ enthusiasm about DDR3, mainboard makers are not as close as excited about the new memory type. Many of system board designers are placing slots for previous generation DDR2 memory even on enthusiast-class platforms, which may delay penetration of DDR3 onto the mass market. But is it actually their fault?
Intel’s new mainstream core-logic sets, such as Intel P35, officially support both DDR2 and DDR3 memory types, but yet unannounced Intel X38 should have supported only DDR3 memory. At least a similar situation happened back in the days of transition to DDR2, when mainstream Intel 915-series supported both DDR and DDR2, whereas premium-class Intel 925X-series sported only DDR2 memory controller. But in reality Intel’s X38 supports dual-channel DDR2 as well.
As the industry prepares to transit to DDR3, many mainboard makers decided to support the good-old DDR2 with their products based on Intel X38 core-logic, but not stick to DDR3, which is currently much more expensive than DDR2.
Albatron, Gigabyte Technology and DFI decided to support on some of their Intel X38-based motherboards only DDR2 memory, whereas Foxconn and MSI decided to install slots for both types of memory onto certain of their Intel X38-based solutions. The mainboards were showcased at Computex Taipei 2007 trade-show and are expected to be available soon. However, it is unclear, what advantages Intel X38 chipset can offer over Intel P35 core-logic in this case, as the former officially supports dual-channel PC3-10600 (DDR3 1333MHz) memory, whereas the latter only officially features support for PC2-6400 (DDR2 800MHz) memory.
DDR3 SDRAM has many advantages of DDR2. For example, DDR3 is able to operate at up to 1600MHz, but in the exchange for enhanced latencies of CAS (column address strobe) 5 to 10 (compared to CAS 3-6 on DDR2). Even though CL7 latency (for 1066MHz clock-speed) setting is considerably higher compared to CL5 of DDR2 at the same frequency, improved pre-fetch and other technical advantages of DDR3 versus DDR2 may help the new memory type to be as fast or even faster compared to the previous-gen one.
DDR3 memory is designed to increase performance and lower power consumption of DDR2 memory utilized today. The new memory standard features relatively low operating voltage of 1.5V, 8-bit pre-fetch architecture (compared to 4-bit pre-fetch buffer with DDR2), on-die termination (ODT), power-saving modes known as PASR (partial array self refresh) and ASR (auto self refresh) and some other capabilities.