DDR2 memory has been the mainstream over the last 3 years. Intel first brought DDR2 into the market when it launched its 9xx series of Express chipsets. These saw DDR2 hitting only 533MHz; originally not much faster than DDR, but we never see high gains in speed on the first series of new products.
Intel have made some questionable decisions in the past, especially in terms of memory support. After the RAMBUS debacle, who really wanted to have another go at the Intel memory path? Luckily for the chip giant, DDR2 paid dividends. While the first DDR2 400MHz incarnations were no faster than their DDR 400MHz counterparts, DDR2 scalability beyond DDR's wildest dreams meant that the faster DDR2 went, the more performance it gained over DDR.
Today we have DDR2 memory modules topping out at 1200MHz DDR2 or 600MHz clock speeds, and this is using only around 2.4v which is within the safe zone. With even more time, cooling and voltage adjustments, more can be possible.
We have five different memory kits for your viewing pleasure, all of them designed to run at speeds beyond DDR2 800MHz for the Athlon 64 X2s and also Intel's P965 and P35 chipsets which have memory support for 800MHz and beyond.
We have been sent two kits from Kingston (a 1GB PC2-6400 and 2GB PC2-9600 kit), a DDR2 1200MHz Kit from Winchip, a DDR2 1200MHz kit from ADATA and also a PC2-9600 2GB kit from Geil. We will be testing each of these kits for stock performance as well as overclocking potential. Which will be our pick? Lets find out.