Intel Core i5 11400F: memory bandwidth analysis
The unexpected highlight of Intel's 11th-gen lineup.
If you missed our 11900K review, let's quickly recap the situation: with the launch of its 11th-gen desktop processors, Intel has finally allowed motherboards built around its cheaper H570 and B560 chipsets to access memory "overclocking", something that was previously only allowed for expensive Z-series boards like Z390 and Z490. This restriction meant that users weren't even able to run their RAM at its rated XMP speeds if this surpassed the previous limit of 2933MHz for Core i7/i9 processors or 2666MHz for Core i3/i5 CPUs - a ridiculous situation.
By relaxing these restrictions, users on more constrained budgets are better able to take advantage of modern high-speed RAM, including the large amount of good value 3200MHz and 3600MHz kits on the market. We've got to give Intel credit for finally making the long-requested change, although we suspect AMD's long-standing policy of not restricting memory speeds by platform (and AMD's rapidly growing market share) is the more likely cause for Intel's shift.
In any case, a greater number of motherboards supporting higher RAM speeds means that it's more critical than ever to know how much extra performance you can actually unlock from a fast memory kit. To answer this, we tested three games at two common frequencies, entry-level ~3000MHz and a common high-tier option, 3600MHz. We're using the exact same sticks and the same timings for these tests (16-16-16-36); just the frequency has shifted here.
First up is Ashes of the Singularity, a DX12 strategy game that absolutely lives and dies on CPU performance, where fast RAM typically sees noticeable performance improvements. Pairing the 11400F with RAM just below 3000MHz resulted in a frame-rate drop of around 15 percent, the largest margin we've ever seen on an Intel system in this test - somewhere between five to 10 percent has been more often in our experience.
Ashes of the Singularity: CPU Test
Far Cry 5 next. This is a single-core-reliant title, so we expect to see a small but noticeable CPU gain from higher RAM - and again our expectations are slightly subverted, with an eight percent improvement from adopting that 3600MHz RAM.
Far Cry 5: Ultra, TAA
Crysis is built very differently, using a much larger number of cores than Far Cry 5, and shows even less of a difference from RAM upgrades. Here, the faster RAM accounts for just a two percent performance differential.
Crysis 3: Very High, SMAA T2X
So based on these results, it looks like fast RAM is quite a key upgrade for the 11400F. However, it's best to take these results with a pinch of salt, as we're using a different motherboard than we normally do, and it may be applying some fine-grained settings differently even though our overall methodology is the same. Regardless, even if the 11400F is only similar to other 10th and 11th-gen CPUs, you can now at least make full use of cheaply available 3000MHz and 3200MHz kits rather than the 2666MHz limits you may have been stuck with on pre-500-series Intel platforms.
Intel Core i5 11400F analysis
- Introduction, hardware breakdown, test system
- Gaming benchmarks: Flight Simulator 2020, Hitman 3, Total War Three Kingdoms
- Gaming benchmarks: CS:GO, Rainbow Six Siege, Black Ops Cold War
- Gaming benchmarks: Cyberpunk 2077, Far Cry 5, Crysis 3
- Gaming benchmarks: Memory bandwidth analysis [This Page]
- Intel Core i5 11400F: the Digital Foundry verdict