DDR4 DRAM memory technology is poised to replace DDR3 later this year. But what exactly is DDR4, and what are its advantages over DDR3? Let’s explore DDR4 and the benefits it brings, with insights from Crucial Memory.
Efficient, Faster, and Higher Capacity Modules
Compared to DDR3, DDR4 technology offers several key improvements:
- Lower Power Consumption: DDR4 operates at 1.2V, reducing power demand. Low voltage versions run at around 1.05V, ideal for mobile devices.
- Higher Capacity: DDR4 modules can reach up to 16GB per stick, compared to DDR3’s 8GB per stick, thanks to higher density modules.
- Increased Speed: DDR4 speeds start at 2133MHz, effectively doubling the 1000MHz standard of DDR3. While DDR4 offers higher speeds, it does introduce increased latency compared to DDR3.
Topology Changes
DDR4’s architecture differs significantly from DDR3:
- Point-to-Point Topology: Unlike DDR3’s Multi-Drop BUS topology, DDR4 uses a Point-to-Point topology. This means DDR4 will only operate in Single Channel with one stick, Dual Channel with two sticks, and Quad Channel with four sticks, limiting upgrade flexibility. For example, a Dual Channel configuration maxes out at 32GB.
Detailed Comparison
Here’s a detailed comparison of DDR3 and DDR4 features:
| Feature/Option | DDR3 | DDR4 | DDR4 Advantage |
|---|---|---|---|
| Voltage (core and I/O) | 1.5V | 1.2V | Reduces memory power demand |
| VREF inputs | 2 – DQs and CMD/ADDR | 1 – CMD/ADDR | VREFDQ now internal |
| Low voltage standard | Yes (DDR3L at 1.35V) | Likely 1.05V | Further power reductions |
| Data rate (Mb/s) | 800-2133 | 1600-3200 | Higher-speed I/O |
| Densities | 512Mb–8Gb | 2Gb–16Gb | Supports larger memory subsystems |
| Internal banks | 8 | 16 | More banks |
| Bank groups (BG) | 0 | 4 | Faster burst accesses |
| tCK – DLL enabled | 300 MHz to 800 MHz | 667 MHz to 1.6 GHz | Higher data rates |
| tCK – DLL disabled | 10 MHz to 125 MHz (optional) | Undefined to 125 MHz | Full DLL-off support |
| Read latency | AL + CL | AL + CL | Expanded values |
| Write latency | AL + CWL | AL + CWL | Expanded values |
| DQ driver (ALT) | 40Ω | 48Ω | Optimized for PtP applications |
| DQ bus | SSTL15 | POD12 | Reduces I/O noise and power |
| RTT values (in Ω) | 120, 60, 40, 30, 20 | 240, 120, 80, 60, 48, 40, 34 | Supports higher data rates |
| RTT not allowed | READ bursts | Disables during READ bursts | Easier use |
| ODT modes | Nominal, dynamic | Nominal, dynamic, park | Additional control mode |
| ODT control | ODT signaling required | ODT signaling not required | Simplified control, non-ODT routing |
| Multipurpose register (MPR) | Four registers – 1 defined, 3 RFU | Four registers – 3 defined, 1 RFU | Additional specialty readout |
Market Readiness
Currently, no existing motherboards or CPUs support DDR4, necessitating new hardware to leverage this technology. Intel’s forthcoming Enthusiast-grade Haswell-E chips will support DDR4, while AMD is expected to introduce support later in 2014, according to JEDEC’s roadmap. As with any new technology, expect initial DDR4 costs to be high.
Intel and several memory manufacturers showcased DDR4 at the recent Intel Developer Forum, indicating that its first widespread use will likely be in servers rather than consumer-grade hardware, with the exception of the soon-to-be-released Haswell-E.
Source: Crucial
The infographic at the top is misinformation, the highest non-OC DDR3 speed is 1866MHZ (1.9~GHZ), currently DDR4 maxes out at 3.6GHZ OC, while factory OC’d DDR3 runs at speeds up to 3.1GHZ out of the box with stock voltage, also, the density is a blatant lie since there are DDR3 DIMMs up to 32GB. Please, for the sake of science correct yourself and do your research better, this article is a shameful display of half-baked facts.
Oh and thus, the chart at the top is completely wrong too, also DDR2 goes up to 800MHZ, not 400MHZ, i would really like it if you explained yourself or improved this article.
DDR2 goes up to 1066 MHz actually, and DDR2 achieved 400 MHz by 2004. Technically, 2004 is also the year when it entered the 533 MHz territory, but 400 MHz is the prevailing speed on that year as far as consumer availability is concerned.
Consumer availability is imo not a good thing to base objective charts on.
The article is older than – when JEDEC released the Non-OC 1866 MHz standard DDR3. Same goes for everything that you have said.
Still makes the charts inaccurate and overproportioned, because OC standards are also supported by many OEMs, and it was not said that this article is in any way exclusive to JEDEC standards, even if that may be the case, there always was 1600MHZ, still rendering this chart inaccurate, sorry for my rude commenting up there, i got a little carried away.