DDR4 vs. DDR5 RAM: What’s the Difference?

Overclocking has also improved, with Intel updating XMP (eXtreme Memory Profile) to 3.0 for DDR5. Where XMP 2.0 only supported two profiles, the newer version has five. Three are set by the memory manufacturer, with two more for you to adjust and edit your settings. Intel hosts spreadsheets with common manufacturers parameters if you are curious about what those profiles look like.

You may have noticed that despite the higher overall clock speed, the latency in DDR5 memory is slightly slower than DDR4. That doesn’t tell the whole story though, and as memory manufacturer Corsair explains“DDR4 usually has a CAS latency of 16, while DDR5 will have a CAS latency of at least 32. However, due to its faster clock speed, the newer standard has better overall performance.” In other words, it takes more cycles to complete a task, but those cycles are much faster than before.

The real Nerdy Stuff

There are a few other changes to the standard for DDR5 that do not really have an impact on which sticks you slot in your particular PC.

DDR5 memory should use less power overall than DDR4, although not in a way that will allow you to get away with a smaller power supply. Instead, it gives manufacturers and overclockers more voltage headroom to push even higher speeds. Each stick of DDR5 memory has its own power management chip now too, rather than the motherboard managing power distribution. Again, probably not something that will matter to most people, but it should result in a more consistent experience when using XMP profiles.

You also get increased bandwidth thanks to a big change to the basic architecture of a memory DIMM. Where each DDR4 module was based on a single 64-bit channel, DDR5 has two 32-bit channels. When combined with increased speed and efficiency, memory maker Crucial says “Users can get up to 2X the system bandwidth compared to DDR4 for next-generation multi-core CPUs.”

Installation slots for random access memory (RAM) computer chips sit on a support board for a server system at Bull SA’s headquarters in Angers, France, Monday, June 23, 2014. Thierry Breton, chief executive of the software producer Atos, is engineering a bid of 620 million euros ($846 million) to acquire Bull, the IT company that has tried to revive two decades ago. Photographer: Balint Porneczi/Bloomberg via Getty ImagesPhotograph: Balint Porneczi/Bloomberg/Getty Images

Some manufacturers also mention Error Correction Code, or ECC, which is now present in DDR5 memory. This is slightly different from ECC in DDR4, which was an extra module present on chips intended for server or commercial use. Instead of helping a bunch of different memory chips communicate reliably, it corrects errors on individual banks before sending them to the motherboard. ATP commercial memory manufacturer has a thorough explanation on the reasoning of this technology that exceeds the scope of what is necessary for your gaming computer, if it is of interest.

Too much to remember?

If you are build a new PCit’s very likely that your motherboard will support DDR5, so that’s what you should buy. The only reason you need DDR4 memory for a new build is if you are specifically using old parts to keep costs down. Most likely you are hunting for DDR4 because you are upgrading an existing system.

In the first days of the launch, you may have paid almost twice for DDR5 over DDR4, but the prices have settled with the more widespread adoption, and will look recognizable to everyone who bought memory before the upgrade.