Buying Guide

DDR5 Memory Explained

Memory is the part where the specification on the box is furthest from what you will actually feel. Three things decide whether a kit was a good buy: how much of it there is, the latency behind the headline speed, and whether anyone remembered to switch the profile on. The third one is free and gets missed constantly.

How Much You Actually Need

32GB is where a gaming build sits comfortably today. It leaves room for the game, a browser with too many tabs open, a chat client and a recording tool without the machine reaching for the drive. Most of our memory kits at this capacity are two modules of 16GB, which is what you want.

64GB is a working decision rather than a gaming one. Video timelines, large scenes, several virtual machines at once, or a machine that simply never gets shut down and accumulates open work across days. If that describes how you use the computer, the extra capacity is the difference between working and waiting. If it does not, the money does more for you on the graphics card.

Buy the capacity as a matched kit of two modules rather than adding to it later. Two modules is what the memory controller is happiest with, and mixing a later purchase with an existing pair is the most common cause of a machine that will not run its rated speed, or occasionally will not boot at all.

Speed, and the Number That Matters

Kits are sold on the transfer rate, the figure in MT/s, because it is the biggest number on the label. On its own it is only half the story. The other half is latency, written as a CL figure, which is how long the memory takes to start answering. Speed is how wide the road is; latency is how long you wait at the junction.

The two work against each other, so a kit with a larger transfer rate and looser timings can answer more slowly in real terms than a tighter kit at a lower rate. This is why 6000MT/s at CL30 is the configuration most gaming builds settle on rather than the fastest kit available. On current AMD platforms there is a second reason: around that speed the memory controller runs in step with the memory rather than at a divided ratio, and pushing past it can cost more than it gains.

The honest caveat: outside a handful of games that are unusually sensitive to it, the difference between a good kit and a faster one is small next to the difference a tier of graphics card makes. Get the capacity and the profile right first, and treat speed as the last refinement rather than the headline.

EXPO, XMP and the Setting People Miss

A DDR5 kit does not run at its advertised speed out of the box. It starts at a conservative baseline that any board can manage, and the rated speed lives in a stored profile that has to be switched on in the firmware. EXPO is the AMD name for that profile and XMP is the Intel one. Many kits carry both.

If nobody enables it, the machine runs perfectly well and noticeably slower than the kit you paid for, and nothing anywhere warns you. It is a single setting in the board firmware. We turn it on for anything we build, and if you are assembling it yourself it is the first thing to check before you conclude the memory was not worth it. Whether a kit carries one profile or both is listed on each of our memory kits, and worth matching to your processor and motherboard.

Common Questions

Will a kit with only EXPO work on an Intel board?
The memory will work, but it will not have a profile to load, so it runs at the base speed rather than its rated one. If your board is Intel, look for XMP on the kit. Several kits list both and are the safe choice if you are undecided on the platform.

Does the height of the modules matter?
Only if you are using a large air cooler, and then it matters a great deal. Tall heat spreaders and wide coolers compete for the same space above the first slot. Tell us which cooler you are planning and we will confirm the clearance, or point you at a low-profile kit.

Should I fill all four slots?
Not if you can avoid it. Two modules is the easier configuration for the memory controller, and four often means settling for a lower speed to stay stable. If you want 64GB, two modules of 32GB is the cleaner way to get there than four of 16GB.

Send us your motherboard and processor, and what the machine spends its day doing, and we will tell you the capacity and profile that suit it. If your cooler is large, mention that too. Availability and pricing confirmed at time of quote.