Kingston Launches Low-Latency DDR3

The technology launch of Intel's new G35 chipset - the first to support DDR3 - occurred just 3 days ago. At launch most reviewers were intrigued by the potential of DDR3 but less than excited about the high latencies and high prices that were available at launch. As you saw in Intel P35: Intel's Mainstream Chipset Grows Up and Intel P35 Memory Performance: A Closer Look our first two samples of DDR3 were rated at DDR3-1066 and 7-7-7-20 timings. These DIMMs would also run at DDR3-1333 with 9-9-9-25 timings. While performance at both speeds was promising, we were left to wonder when lower latency DDR3 might become available.

The higher latency DDR3 at launch certainly gave the top DDR2 a run for the money, but it generally took much higher speeds to match or surpass current DDR2 with low latency timings. It was clear lower latency would bring DDR3 much improved performance and make it even more attractive to buyers, but we assumed it would likely be months until we saw lower latency DDR3 - as it was in the launch of DDR2.

With this scenario, imagine our surprise when Kingston asked us if we would like to review their first low-latency DDR3. Where the competition was 9-9-9 at DDR3-1333 and 7-7-7- at DDR3 1066, Kingston specified their new DDR3 memory at 7-7-7 at 1333 and 6-6-6 at 1066. These were definitely some memory sticks we wanted to review.

If these numbers still seem high to you, you need to back up a bit for a larger perspective. While lower speed DDR2 can have latencies as fast as 3, DDR3 starts at 800 and the boards we have seen only allow CAS latencies as low as 5. The CAS range on better P35 boards is normally 5 to 10. Given this range of available latencies at higher speeds than DDR2, it is clear the new Kingston KHX11000D3llK2/2G has found ways to provide the lowest latencies so far in DDR3.

Keep in mind that the actual latency in nanoseconds is what really matters, so while the number of memory cycles from DDR2-533 CL3 through DD2-667 CL4, DDR2/3-800 CL5, DDR3-1067 CL7, and DDR3-1333 CL9 increases, the actual latency in ns only ranges from 11.25ns (DDR2-533 CL3) to a maximum of 13.5ns (DDR3-1333 CL9). While CL7 may sound like a high latency, achieving that with 1333 MHz memory is actually results in a time latency of 10.5ns, and of course that's with much higher bandwidth than some of the other memory speeds.

We presented detailed comparisons of memory performance on the current P965, DDR2 on the P35, and DDR3 on the P35 just last week. This allowed us to run a full suite of comparison tests using the same configurations used in Intel P35 Memory Performance: A Closer Look. Those wondering whether DDR3 can compete with low-latency DDR2, and when that might happen will get some answers to their questions in this comparison.