Advanced Micro Devices Inc (AMD)

[sgolds]

kpf, that is basically right. Since DDR-266 is called PC2100, it is likely that DDR2-533 will be called PC4300 (they like to round to whole 100s). The industry seems to be skipping DDR2-400 and going directly to the faster clock rate, although I note on Micron's web site that they are offering DDR2-533 for both 533 and 400MHz applications.

http://www.micron.com/products/dram/ddr2sdram/

(I like Micron's terminology, it is very clear from 400 Mb/s/pin and 533 Mb/s/pin data rates exactly what they mean.)

Thus it is possible for the first socket 939s to use either DDR-400 or DDR-533 timings, if they do use DDR2. They may design intending the faster speed but leave the final decision to test results, or offer the highest speed only for unregistered parts. We really have very little from AMD on this topic, I'm only speculating based on industry trends.