I'm upgrading from a Ryzen 7 7800X to a Ryzen 7 7800X3D with an MSI B650 motherboard. I understand the basics of building PCs, but I'm less sure how RAM speed and latency affect this platform. I want the minimum sensible specification that won't noticeably hold back the processor without paying unnecessarily high prices. I've seen 5200MHz memory with CL30 timings and wonder whether that is worth considering, or if I should aim higher. Since I'll mainly be gaming at 1080p, does that change the recommendation? I'd prefer to spend around £200, with an absolute maximum of £300, and I'm open to either new or used memory.
3 Answers
For Ryzen 7000, DDR5-6000 is generally the best target because it offers a good balance of performance, stability, and price. CL30 is ideal, although CL32 is also perfectly reasonable if it costs less. A 6000MT/s CL36 kit can still work well with the 7800X3D, especially if the price difference is significant. Make sure you buy a matched kit, preferably 32GB as 2x16GB, and enable the EXPO profile in the motherboard BIOS.
A practical shopping range would be 32GB of DDR5-6000 with CL30–36 timings and AMD EXPO support. Don’t overpay for extremely tight timings; moving from CL30 to CL32 or CL36 is unlikely to transform gaming performance. Comparing warranty coverage is sensible when buying used, since a retailer-backed warranty can be worth paying a little extra for.
DDR5-5200 CL30 won’t cripple the system, but it isn’t the usual sweet spot for this CPU. The difference between 5200 and 6000 is usually modest in games, and the 7800X3D’s large cache helps reduce the impact, so 5200 CL30 may be worth considering if it is substantially cheaper. At 1080p, memory differences can show up more often because the CPU is less likely to be hidden behind GPU limits, but the real-world gap is still generally small.

If I dropped to a slower kit or accepted higher latency, would the performance loss be noticeable?