One of the more exciting aspects of Intel’s upcoming 12th Gen Core “Alder Lake-S” processors is their support for DDR5 memory, which promises a significant boost in bandwidth and data rate versus its predecessor. New benchmarks spotted by hardware leaker harukaze5719 provide some insight as to what this exciting combination might bring for enthusiasts who decide to upgrade to blue team’s latest and greatest.
The benchmark stems from a system leveraging a 12th Gen Intel Core i5-12600K (10C/16T) processor clocked at 4.59 GHz with DDR5 memory running at 6,400 MHz. The memory is shown with a read speed of around 90 GB/s, write speed of around 88 GB/s, and copy speed of around 77 GB/s. These bandwidth figures are pretty impressive, but the latency seems worrisome at 92.5 ns.
[AIDA64 Memory Benchmark]— 포시포시 (@harukaze5719) September 13, 2021
i5 12600K + DDR5-4800MHz config? 🧐🧐🧐 pic.twitter.com/jt78M518U4
In the last decade, Intel hasn’t released a single architecture that approached 92.5 ns of memory latency. Only AMD’s original Zen architecture was capable of such laggy behavior, and it was known for its memory bottlenecks in that first-generation iteration.
The reason for this increased latency seems to relate to Intel’s new Gear 4 mode, which the DDR5 memory in this test is reportedly running at. Gear 1 and Gear 2 models were introduced as part of the Rocket Lake generation to improve memory support, with the former running the memory controller and RAM at the same frequency for lower system latency and the latter reducing the memory clock to a 2:1 ratio in order to reach higher frequencies and bandwidth.
Intel’s new Gear 4 mode goes even further by reducing the memory controller frequency to a quarter of the memory frequency, which, while improving support for faster memory, evidently increases latency by quite a bit.
Source: harukaze5719 (via Tom’s Hardware)