DDR4 vs DDR5 Comparison
Compare DDR4 and DDR5 on bandwidth, latency, real gaming impact and price, and see which memory generation makes sense for your build.
DDR4 or DDR5 - which do you need?
You rarely get to choose. The motherboard decides: AM5 is DDR5 only, AM4 is DDR4 only, and LGA1700 exists in both variants. The two are physically keyed differently and electrically incompatible, so the question is really which platform to buy, not which memory.
Why DDR5's higher CAS numbers are not slower
DDR4 at CL16 and DDR5 at CL30 look far apart until you convert to actual time. CAS latency counts clock cycles, and DDR5's clock is much faster, so each cycle is shorter. True latency in nanoseconds is the honest comparison:
true latency (ns) = CAS ÷ (MT/s ÷ 2) × 1000
DDR4-3600 CL16 works out to about 8.9 ns and DDR5-6000 CL30 to about 10 ns — so DDR4 still holds a small latency advantage, while DDR5 offers far more bandwidth. Which matters depends on the workload.
What DDR5 actually brings
- Bandwidth — roughly double, which helps integrated graphics, content creation and heavily threaded work.
- Two sub-channels per module — better parallelism, and the reason a single DDR5 stick is less catastrophic than a single DDR4 one.
- On-die ECC — corrects internal errors. This is not full system ECC, but it improves stability at high densities.
- Higher capacities — 48 and 64 GB modules exist, so 128 GB is achievable with two sticks.
Is it worth upgrading?
For gaming, the difference is usually 0–8% depending on the processor. That does not justify replacing a working DDR4 platform, since it means a new CPU and motherboard too. For a new build, DDR5 is the obvious choice — it is now similarly priced and it is where all future platforms are going.
Enable your profile
Whichever generation you have, memory runs at a slow JEDEC default until EXPO (AMD) or XMP (Intel) is enabled in the BIOS. Check the rest of your configuration with the RAM Compatibility tool.
Frequently asked questions
Is DDR5 worth it over DDR4?
For a new build, yes - prices have converged and every new platform uses it. For an existing DDR4 system, no: upgrading means a new CPU and motherboard for a single-digit gaming gain.
Why does DDR5 have higher CAS latency?
CAS counts clock cycles, and DDR5's clock is much faster, so each cycle is shorter. DDR5-6000 CL30 has similar real latency to DDR4-3600 CL16 while carrying far more bandwidth.
Can I put DDR4 in a DDR5 motherboard?
No. The notch position differs and the electrical design is incompatible. A board supports one or the other, never both.
What is the DDR5 sweet spot?
6000 MT/s CL30 for AMD, where it matches the infinity fabric ratio, and 6400 MT/s or higher for Intel, which is less sensitive to that relationship. Going far beyond either costs a lot for very little.
Does DDR5 need to be enabled in the BIOS?
The rated speed does. Without EXPO or XMP enabled, a 6000 MT/s kit runs at 4800 - the JEDEC default. This is the most common reason people see no benefit from fast memory.