On a speed level, it seems that DDR3 modules start from where the fastest DDR2 modules left off. DDR3 PC3-6400 (800MHz) and DDR3 PC3-8500 (1066MHz) are offered as ‘mainstream’ modules and PC3-1067 (1333MHz) and above are currently offered as high speed overclocking RAM. The best enthusiast DDR2 modules are currently struggling to reach 1250MHz and require voltage settings much higher than the 1.8V DDR2 standard. DDR3 timings appear considerably inferior to those of high-performance DDR2 modules but they are not directly comparable since the 8-bit pre-fetch buffer and the introduction of more technologies (such as power saving features, i.e. the auto self refresh and partial array self refresh) has them doing more things per cycle. PC3-12800 (1600MHz) modules are already being released to the market, so we feel that it won’t be late before we witness 1866MHz and even >2GHz modules available for sale, but it will certainly take several months, perhaps even years for DDR3 to overthrow DDR2 modules in the mainstream market. DDR2 RAM production is not going to decrease in the following months at the very least.



Link: Driverheaven