If you're building a PC today or picking up a mini PC or laptop, you'll likely be using DDR5 memory. It's been a while since a CPU that supports DDR4 was released; all the current motherboard chipsets only support DDR5, and it's now a mature technology pushing the boundaries of what the specifications promise.

The march of progress never slows, and DDR5's successor is already in the works. DDR6 is currently in the draft stages, with an estimated timeline of platform validation in 2026, and usage in the data center in 2027. With the usual trickle-down effect, it could be 2028 or 2029 before we see it on the desktop, which is a good thing because we'll need some time to get used to the new form factor that will come in.

What's so different about DDR6?

New sub-channel architecture enables huge speed boosts (and added signaling issues)

DDR6 uses an all-new 4×24-bit sub-channel architecture, which enables crazy-fast speeds and lots of bandwidth, but brings new challenges for signal integrity. With a JEDEC minimum target of 8,800 MT/s, and plans to scale up to 17,600 MT/s (and extension to 21,000 MT/s), the only thing that's certain at this stage is that it needs a new approach to the physical design.

Currently, all desktop memory uses PAM (pulse-amplitude modulation) for signaling, but this is already stretched with DDR5's higher speeds. JEDEC might change to the NRZ (non-return to zero) standard instead, but this is one of the questions to answer before the DDR6 specification is finalized.

Expect the unexpected

It's likely that DDR6 memory modules will get more of their power delivery circuitry moved to on the modules, where the motherboard currently handles those needs. Doing conversions near to the NAND means cleaner power, better efficiency and improved reliability. This already started with DDR5 bringing on-die ECC memory correction, supplementary clock generators, and some of the voltage delivery, and I expect that will continue to happen with DDR6 as it gets closer to a physical release.

New problems mean new solutions

We might see widespread adoption of CAMM2 modules on the desktop

JEDEC has announced that DDR6 RAM and LPDDR6 RAM will use the new CAMM2 form factor, which puts the RAM module parallel to the motherboard. That means that at this stage, the next memory modules for computers will drop the DIMM and SO-DIMM form factors that we've used for so many years now. One reason for this change is that the current T-topology of motherboard memory slots is causing signaling issues with DDR5 once you get to higher speeds.

CAMM2 solves this in two very simple ways. It removes the soldered connections used in DIMM slots, which create enough radio interference when powered that they can drop the maximum speed of RAM by up to 400 MT/s. Then it moves the topology onto the CAMM2 module, removing the issue altogether as it's designed for, and the signal path can be adjusted for peak performance.

It does mean motherboards need redesigning, but it also opens the door to smaller form factors as you could conceivably put the memory connector on the back of the motherboard. And current implementations require several screws to hold the module down, but JEDEC is working on toolless ways to implement this as well.

Or maybe soldered-on solutions

We'll also likely see a lot more laptops and mini PCs with soldered-on memory. While that means no upgrade path for the user, signaling issues can be mitigated at the design stage, instead of working around the limitations of removable modules. Intel's Lunar Lake, Apple's M-chips, and AMD's Strix Halo are good examples of how this would work in practice, and for those who like to upgrade their computers down the line, it's unfortunately going to mean that it's not possible.

Or a new DIMM form factor altogether

The draft specs for DDR6 are just that: they haven't been finalized yet. We're still a few years out from consumer products with DDR6. Still, the datacenter will be getting it first, and that means the specifications are nearly final, as the industry will need to undergo platform validation before widespread usage. And sometimes the needs of the data center mean different form factors that don't make it to the desktop, like DDR5 MRDIMMs (multiplexed rank dual inline memory modules) that can put 256GB of memory on one module.

Whatever form it takes, DDR6 is going to be beastly for desktop users

With a JEDEC standard starting from 8,800 MT/s, DDR6 is going to be blisteringly fast for desktop use. That, coupled with the higher capacity NAND that's in the works will mean plenty of bandwidth and capacity for gaming, AI workloads, and creative content making, but it will also come with the need for new motherboards, new CPUs, and a new way of building PCs.