DDR2 Roundup: Reaching for 667 and Beyond

@ 2004/07/08
Each time we had approached the launch date for Intel's new 925X/915 chipsets, we ran into delays. The rumors seemed to be consistent that there were still issues with DDR2 memory for the new platform, and almost everyone with whom we talked had described the difficulties with getting the new DDR2 memory working as it should.

Against that background, it is positively amazing that we find such a broad selection of DDR2 memory just a couple of weeks after the launch (finally) of the new Intel architecture. While we received the first samples of DDR2 memory over 3 months ago, it is clear that development has continued over the past few months. We had already found that DDR2 533 performed about the same as fast DDR433 in our 925X/915 launch review using the Intel D925XCV. While this is not the 1:1 to DDR533 that many hoped for, it is still an excellent improvement in performance over the early results with DDR2. However, Intel motherboards are not traditionally geared toward pushing memory to even higher performance than specification, and we also had to contend with the limitation of the Intel 10% overclock lock that is engineered into the 925X/915 chipsets.

However, with the Abit AA8 and Asus P5AD2 known to have found ways around the 10% lock, it was time to take a closer look at the performance of DDR2. Other 925X motherboard manufacturers, such as Gigabyte and MSI, are also rumored to have broken the 10% lock. With a little more open route above a 220FSB setting, it now made sense to look at the current state of DDR2 memory performance. In particular, we were interested in seeing how far current DDR2 memory would need to develop to reach the magic DDR667 that will be needed for the next speed ramp of the Intel architecture within the next few months. The answers may surprise you.

Comment from Sidney @ 2004/07/09
There will be more to come in weeks ahead on the same.
Comment from calantak @ 2004/07/09
Interesting...

quote : "As you can see clearly, over the full range of tRAS 4 to tRAS 13, there is virtually no difference in memory performance when tRAS is adjusted. While there is a slight falloff at tRAS of 14 and 15, it is still minor. We can conclude that a tRAS setting of 4 to 13 makes no difference in memory performance. Since higher tRAS settings usually mean better memory stability, we can well understand why a 12 setting is standard. For our memory tests, "we chose a value of 10, which represents the upper mid-range of best performance and stability. However, we did find that some high density (1GB) memory modules that were not included in our tests performed with greatest stability at a tRAS setting of 11 or 12. Overall, we had no difficulties at tRAS 10, but there is no performance penalty when using 11 or 12, if it improves the stability of your DDR2 memory."


The most amazing test results came from all the new DDR2 memories that we tested. Amazing, in that even the cheapest value DDR2 ran with complete stability at DDR2 667, which is the next major speed in the DDR2 highway. In addition, every one of the eight memories that we tested in this roundup ran with complete stability at the highest FSB which we could support on any current 925X motherboard - DDR2 686. Most of the tested DDR2 even accomplished this overclocking feat with much better than standard 4-4-4-10 timings and a modest voltage increase to 1.9V from the default 1.8V. "
But that still leaves them far from conquering their ddr1 friends