AMD 5900X and Ryzen 7 5800X: Memory bandwidth analysis

One of the most fascinating characteristics of the AMD Ryzen platform from the beginning has been its reliance on high-speed RAM in order to make up for the inherent latency disadvantage the platform faces due to its chiplet architecture. Third-gen Ryzen processors added much larger L3 caches, helping to ameliorate the problem, while Ryzen 5000 packs more cores into a single complex to minimise the amount of data that needs to travel across the Infinity Fabric to reach cores in a different complex. Therefore, it's interesting to see whether high-speed RAM is as crucial to include in Ryzen 5000 builds as it has been in earlier Ryzen versions.

AMD allows for RAM overclocking even on its inexpensive motherboards - something not permitted on Intel's non-Z platforms - and RAM kit costs continue to fall, so outfitting your own system with fast memory is relatively affordable. In these tests, we'll look at two titles we tested earlier, Crysis 3 and Far Cry 5, plus real time strategy game Ashes of the Singularity, to see how much performance you gain from switching from commonly available 3000MHz RAM to higher-grade 3600MHz RAM with the same timings.

In Ashes of the Singularity, we see around a five per cent jump in performance for both of the Ryzen 5000 processors in today's tests, which is a little less of a difference than the seven or eight per cent lead we've come to expect from Ryzen 3000 processors. The actual frame-rates here are also remarkable, with the 5900X beating the Core i9 10900K by an eight per cent margin and the 5800X outdoing the Core i5 10600K by 16 per cent (!).

You gain around four per cent more performance from switching from 3000MHz to 3600MHz in Far Cry 5, which is around average for Ryzen 3000 but not as large as we've seen from some other processors. Crysis is a good example of a game that doesn't really benefit from faster RAM, as the result here is around one per cent.

AMD Ryzen 9 5900X and Ryzen 7 5800X analysis

• Introduction, hardware breakdown, test system
• Gaming benchmarks: Assassin's Creed Odyssey, Battlefield 5, Far Cry 5
• Gaming benchmarks: Crysis 3, Metro Exodus, Kingdom Come Deliverance, The Witcher 3
• Gaming benchmarks: Memory bandwidth analysis [This Page]
• AMD Ryzen 9 5900X and Ryzen 7 5800X: the Digital Foundry verdict