GoKawiilAMD's EXPO Ultra Low Latency program, announced at Computex 2026, aims to give users a one-click route to lower memory latencies than its existing EXPO profiles, but the company's initial announcement was light on details. To learn more about EXPO ULL, I stopped by G.Skill's Computex booth, where the company demonstrated four new kits that offer EXPO ULL support.
Memory latency directly affects how long the CPU has to wait in order to get data back from RAM, and so it has a major impact on CPU performance. But even as new DDR standards and ever-faster DIMMs have boosted memory bandwidth, DDR latency has improved at a much slower pace over time.
For some very high-level background, when selecting memory, PC builders will generally consider a given memory kit's speed and its CAS latency (CL). If you compare two CL30 memory kits, for example, the one with the higher clock rate will have a lower effective latency in nanoseconds (because CL30 expresses a number of clock cycles).
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Knowing this, your first instinct for reducing latency might be to seek the highest-clocked memory you can find with the lowest CAS latency (like DDR5-8400 or even faster modules).
But on modern AMD platforms, it's not that simple. Reaching memory speeds higher than 6000 MT/s generally requires the use of a 1:2 multiplier mode between the clock of the integrated memory controller (the UCLK), which generally tops out around 3000 MHz, and the memory clock (MCLK). This 1:2 multiplier adds latency, and so it can counterintuitively reduce performance even as memory speeds climb above 6000 MT/s. (Remember that DDR memory moves bits at twice the clock rate, hence MT/s).
With this 1:2 multiplier active, by the time additional memory clock speed even begins to bring latency back down to where it would generally be in the 1:1 mode, you're looking at wildly expensive and exotic memory kits, and so most enthusiasts running Ryzen 7000 and Ryzen 9000 CPUs consider it desirable to choose memory that lets them run the UCLK and MCLK in 1:1 lockstep for the best balance of low latency and (relatively) low cost.
All that is why using memory faster than 6000 MT/s on AMD platforms is generally counterproductive for gaming performance. That's why modules in the range of DDR5-6000 CL30 are widely regarded as the overclocking "sweet spot" for Ryzen 7000 and Ryzen 9000 CPUs.
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But that doesn't mean there isn't further room for improvement, as the introduction of EXPO ULL suggests.
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