Tweaking for Speed

With testing out of the way, I endeavored to see if these sticks have any tuning headroom. For Intel, I kept the same procedure, leaving all settings at their XMP defaults and then increasing the frequency until the system loses stability. After finding that limit, I manually tweaked for the maximum frequency. Voltage modification from stock is allowed. After all, this is overclocking!

A good starting point for Ryzen Zen 3 based builds is 3600–4000 MT/s, due to Infinity Fabric limitations. For those unaware, AMD Ryzen CPUs can benefit substantially from a synchronized 1:1 ratio with system memory and Infinity Fabric. This extends to the Ryzen 3000 series as well, though peaking around 1900 MHz instead to keep the 1:1 ratio intact. This is slightly lower than the Ryzen 5000 series, but still preferred over the 2:1 ratio configuration.

On the Intel side of things, 8th to 10th Generation Intel Core processors are going to benefit the most from the highest-possible frequency with the lowest timings. That being said, 3733–4000 MT/s is the ideal target range since there is no need to play around with VCCSA/IO voltages, and it is mostly plug and play. Switch to an 11th Gen Intel Core processor and things change given the introduction of the memory controller Gear ratio similar to what AMD has done. Once you surpass the memory controller's ability to stay in synchronous 1:1 mode, most motherboards will automatically switch to 2:1 ratio. If all else fails, you can manually set this in the BIOS.

With the release of Intel's 12th Gen Intel Core processors, not much has changed from the fundamentals introduced in the previous 11th generation. However, the biggest change here is the i9-12900K CPU. With a bit of IMC voltage tuning, it can reach 4000 MT/s while keeping the 1:1 ratio to the memory controller. Updating the BIOS to the latest available is important, as stability issues are progressively resolved.

Getting this Neo Forza MARS XMP profile of DDR4-4000 to operate in Gear 1 mode with auto settings will greatly depend on the motherboard used, and the CPU memory controller. Seeing as this is dual-rank memory (i.e., two-sided DIMM and two pools of addressable memory), it is more stressful on the CPU memory controller than two single rank sticks, being equivalent to four single rank sticks, with the advantage of having two fewer memory traces needed. By default the memory typically adjusts to Gear 2 (2:1) for compatibility.

Intel Results

Since 2000 MHz (Gear 1) will be a challenge to get working stably, I figured focusing on lower frequencies and tightening primary timings was a better choice. Due to the module density already limiting overclocking, the session was quick. In this instance, considering the use case for this memory kit, raising the voltage is not advised. I cannot recommended voltages above the 1.4 V safely used in the XMP profile.

What this "overclock" does provide is tighter timings, combined with a slightly lower frequency, performance rivals the XMP profile. What makes this tune superior is the fact that DDR4-3800 (Gear 1) will be more obtainable for users.