Updated August 12, 2026 · reviewed against primary sources
Comparison
DDR6 vs DDR5
Every DDR generation makes the same three promises: roughly double the bandwidth, same-or-lower voltage, and a new platform to buy. DDR6 is on script. The useful comparison isn't the spec table — it's understanding when the doubling becomes real for a machine you can own, because generational transitions have a well-documented shape and it's slower than the headlines imply.
Three generations, one table
| DDR4 | DDR5 | DDR6 (targets) | |
|---|---|---|---|
| Spec published | 2012 | July 2020 | expected 2026 |
| Consumer platforms | 2014–15 | Nov 2021 | realistically 2027+ |
| Launch data rate | 2,133 MT/s | 4,800 MT/s | ~8,800 MT/s |
| Mature data rate | 3,200+ (JEDEC) | 6,400+ JEDEC · 8,000+ enthusiast kits | up to ~17,600 MT/s |
| Channels per module | 1 × 64-bit | 2 × 32-bit sub-channels | finer granularity expected |
| Voltage | 1.2 V | 1.1 V | ≤ 1.1 V expected |
| ECC | module-level option | on-die ECC standard | at least DDR5's posture |
The part that matters: launch parts vs. mature parts
Note the pattern in that table. A generation's launch speed roughly equals the previous generation's mature speed. DDR5 opened at 4,800 MT/s when tuned DDR4 was running 3,600+; early DDR5 also carried looser timings, so real-world wins were modest for a year. Expect the rerun: first DDR6 kits near 8,800 MT/s against mature DDR5 kits at 8,000+, at a large price premium, on first-generation platforms. The people who win a memory transition are rarely the ones who buy year one.
Where DDR6's doubling will matter first
- Servers and AI inference boxes — bandwidth-per-socket is the binding constraint; this is why enterprise adopts first.
- Many-core desktops — finer sub-channels feed more cores concurrently, which is the quiet win beyond the headline MT/s.
- Local LLM inference — token generation is bandwidth-bound; see why bandwidth gates LLM inference. DDR6 will genuinely help here — in 2027+, on new platforms.
So: build DDR5 now, or wait?
If you need a machine inside 18 months, the answer is DDR5 and it isn't close — you'd be waiting a CPU generation for launch-priced modules on rev-1 boards. The full decision page runs scenarios; best DDR5 for local AI covers the build that actually benefits from getting memory right today.