DDR-2, like most new technology that is here to stay, is something that has to be proven over time. DDR so far has the upper hand, as its lower latencies and bandwidth matching performance shows that higher bandwidth in theory isn't always better, but to be frank it is hard to draw definite conclusions from this due to a number of factors.
First we are dealing with first generation DDR-2 modules as well as first generation DDR-2 motherboard chipsets. DDR didn't fully blossom until the third and forth generation chipsets started to take advantage of this new technology, and they have had since 1999 to the present day to perfect this technology, and perfect it they have.
Second we are dealing with only one platform that has a nature of starting out slow and building up, after all, Pentium 4 when it first came out wasn't any faster than the Pentium 3, but we can't say that today, with the performance of the P4 now being at the 4GHz doorstep we see that the architecture is developed into a usable source, which is what DDR-2 must do.
We can only hope that the upcoming 1066FSB Pentium 4 and 925XE chipsets have better optimisations for DDR-2, as the extra bandwidth of DDR-2 at 533MHz is simply wasted, where it should be used for graphics card use or other high bandwidth systems, after all the P4 has its 6.5GB/s, the rest on the current 9xx chipset just wastes the remaining 2GB/s.
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