The new kid on the block is DDR3, with high frequencies, but also high timings.  TweakTown tries out a set of 1066 DDR2 and DDR3 DIMMs by overclocking the DDR3 to 1333 and 1500 with the best timings they can manage, and going gaming.  You can get a good idea as to whether the technology is mature enough that you want to switch, or stay with high speed DDR2.
“DDR-3 makes the decision even harder as it carries an extreme cost at the moment but do those dollars actually translate into extreme gaming performance? Technically speaking, in pure megabytes per second, it is fast, thanks to the attainable speeds 1500MHz double data rate and beyond which can be achieved, without too much effort. However, the big issue with DDR-3 memory right now is the fact that its latency is high, much higher comparatively to more finely tuned DDR-2.”

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