DDR4 vs DDR5
Published: Updated:
Spec-based comparison. We have not tested these products. Figures below come from the linked manufacturer datasheets and standards documents.
Short verdict
Your CPU and motherboard decide for you. DDR4 and DDR5 modules are not interchangeable: a board takes one or the other. AM5 processors such as the AMD Ryzen 5 9600X support DDR5 only; LGA1700 processors such as the Intel Core i7-14700K support DDR5 or DDR4, and the motherboard determines which. If you are building a new AM5 system, the choice is DDR5. If you are upgrading an existing DDR4 board, the choice is DDR4.
Key differences
| DDR4 | DDR5 | |
|---|---|---|
| Data rates (JEDEC) | up to 3200 MT/s | 4800 MT/s and up; Micron lists up to 8800 MT/s |
| Supply voltage (VDD / VDDQ) | 1.2 V / 1.2 V | 1.1 V / 1.1 V |
| VPP | 2.5 V | 1.8 V |
| Prefetch / burst length | 8n / BL8 | 16n / BL16 |
| Bank groups | 4 | 8 |
| Channels per module | 1 | 2 independent subchannels |
| On-die ECC | no | yes (128 data bits + 8 check bits, single-error correction) |
| Power management | on the motherboard | PMIC on the module |
| Die densities | 2–16 Gb | 16–32 Gb |
Sources: Micron, DDR5 SDRAM; JEDEC, DDR5 standard press release.
What the differences mean
Speed. DDR5 starts where DDR4’s standard speed grades end. More transfers per second mean more bandwidth, which helps workloads that move a lot of data through memory. Whether a game runs faster depends on the game and the rest of the system — we will only quote game results after measuring them ourselves.
Two subchannels per module. JEDEC splits each DDR5 module into two independent subchannels. Together with the longer burst length, this lets the memory controller keep more requests in flight.
On-die ECC is not “ECC memory”. DDR5’s on-die ECC corrects single-bit errors inside the memory chip. It does not replace ECC modules (with extra chips) that protect data on the way to the CPU. If you need full ECC, buy modules and a platform that explicitly support it.
Latency in nanoseconds. CAS latency (CL) is counted in clock cycles, so higher CL numbers on DDR5 do not automatically mean slower access. A simple conversion is: latency (ns) = CL × 2000 ÷ data rate (MT/s). DDR4-3200 CL16 and DDR5-6000 CL30 both work out to 10 ns — the formula is arithmetic, not a benchmark.
Platform support (examples from manufacturer spec pages)
| Processor | Memory type | Max rated speed |
|---|---|---|
| AMD Ryzen 5 9600X (AM5) | DDR5 only | DDR5-5600 with 2 modules; DDR5-3600 with 4 modules |
| Intel Core i7-14700K (LGA1700) | DDR5 or DDR4 | DDR5-5600 or DDR4-3200 |
Sources: AMD Ryzen 5 9600X specifications; Intel Core i7-14700K specifications.
Note the AMD figure: with four DDR5 modules the rated speed drops. Two modules are the usual way to reach a kit’s rated speed on dual-channel desktop platforms.
Which should you buy?
- New AM5 build: DDR5 — it is the only option.
- Intel LGA1700 (e.g. Core i7-14700K): check your motherboard’s specification page; it supports one memory type, not both.
- Upgrading an existing DDR4 system: DDR4 — a DDR5 kit will not fit.
Price comparisons for both generations: nandprices.com.
FAQ
Can I put DDR5 in a DDR4 slot? No. Micron states that DDR4 and DDR5 are not cross-compatible, and the module notch sits in a different position, so a DDR5 module does not fit a DDR4 slot.
Does DDR5 use less power? It runs at a lower nominal voltage (1.1 V vs 1.2 V), and voltage regulation moves onto the module. Actual system power depends on speed and workload; we have not measured it.