Overclocking has improved as well, with Intel updating XMP (eXtreme Memory Profile) to 3.0 for DDR5. Where XMP 2.0 supported just two profiles, the newest version boasts five. Three are set by the memory manufacturer, with two more for you to tweak and edit your own settings. Intel hosts spreadsheets with settings from common manufacturers if you’re curious what those profiles look like.
You may have noticed that, despite overall higher clock speeds, the latency on DDR5 memory is a bit 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, because of its faster clock speeds, the newer standard has better performance overall.” 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 don’t really impact which sticks you slot in your particular PC.
DDR5 memory should use less power overall than DDR4, although not in a way that will let you get away with a smaller power supply. Instead, it gives manufacturers and overclockers more voltage headroom to push for even higher speeds. Each stick of DDR5 memory has its own power management chip now too, rather than the motherboard handling 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 relied on a single 64-bit channel, DDR5 has two 32-bit channels. When combined with the increased speed and efficiency, memory manufacturer Crucial says “users can get up to 2X the system bandwidth compared to DDR4 for next-gen, multi-core CPUs.”
Installation slots for random access memory (RAM) computer chips sit on a support board for a server system at the Bull SA headquarters in Angers, France, on Monday, June 23, 2014. Thierry Breton, chief executive officer of software maker Atos, is engineering a 620 million-euro ($846 million) bid to acquire Bull, the computer company he 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 on DDR5 memory. This is a little bit different from the ECC on 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 the individual banks before sending it off to the motherboard. Commercial memory maker ATP has an in-depth explainer on the reasoning for this tech that goes beyond the scope of what’s needed for your gaming computer, if that’s of interest.
Too Much to Remember?
If you’re building a new PC, it’s extremely likely your motherboard will support DDR5, so that’s what you should buy. The only reason you’d need DDR4 memory for a new build is if you’re specifically using old parts to keep costs down. It’s more likely you’d be hunting for DDR4 because you’re upgrading an existing system.
In the early days of the launch, you might’ve paid almost twice as much for DDR5 over DDR4, but prices have settled with more widespread adoption, and they’ll look recognizable to anyone who bought memory before the update.
