DDR4
Double data rate fourth generation (DDR4) is a memory standard designed as a better, faster, more reliable replacement for DDR3
Key Features
- Density: 2 GB to 128 GB
- Increased performance and bandwidth (up to 3200 MT/s)
- Decreased voltage for better power consumption
- Provides better reliability, availability and serviceability (RAS) and improves data integrity
- Lower signalling standard
- Reduced power x8 Prefetch
- Dynamic ODT for improved write signalling
- Fly-by architecture
- Read/Write Levelling
- Driver calibration
- Device Reset
- DIMM address mirroring
- Improved device pinout
DDR3
Double data rate Third generation (DDR3) is a memory standard designed as a better, faster, more reliable replacement for DDR2
DDR3 Key Features
- Density: 1 GB to 32 GB
- Chipkill support
- Fly-by command/address/control bus with on-DIMM termination
- Higher bandwidth performance, effectively up to 1866 MT/s
- Better performance at low power; 1.5V (Normal) and 1.35V (Low Voltage)
- Lower signaling standard Reduced power x8 prefetch
- Dynamic ODT for improved write signaling
- Fly-by architecture
- Read/Write Levelling
- Driver calibration
- Device reset
- DIMM address mirroring
- Improved device pinout
How does DDR4 differ from DDR3 in appearance?
Physically, a DDR4 module, or dual in-line memory module (DIMM), looks very similar to a DDR3 DIMM. However, DDR4 has 288 pins compared with DDR3’s 240 pins; DDR4 SO-DIMMS have 260 pins instead of 204 in DDR3. The DDR4 key notch is in a different place, and the edge connector looks like a slightly curved “V” to facilitate insertion. This design also lowers insertion force, as not all pins are engaged at the same time during module insertion.
| DDR3 | DDR4 |
|---|---|
| DDR3 RAM stands for Double Data Rate version 3. | DDR4 RAM stands for Double Data Rate version 4. |
| DDR3 RAM was introduced in 2007. | DDR4 was reading released in 2014. |
| The cost of DDR3 is lesser than DDR4. | DDR4 cost is higher or more than DDR3. |
| DDR3 consumes less power than DDR2 but more than DDR4. | DDR4 consumes less power than DDR3. |
| The speed of DDR3 is slow in comparison to DDR4. | DDR4 speed is faster than DDR3. |
| DDR3 maximum memory size is 16 GB. | DDR4 has no maximum limit or capability. |
| The clock speed of DDR3 varies from 400 MHz to 1066 MHz. | The clock speed of DDR4 varied from 1066 to 2133 MHz. |
| DDR3 has lower latency than DDR4. | DDR4 has more latency than DDR3. |
| DDR3 has lower latency | DDR4 has more latency than DDR3 |
| Auto-refresh and self-refresh are performed for content. | Only self-refresh is performed for a content. |
| DDR3 RAM includes ECC memory, which compresses extra data byte lanes. | DDR4 RAM offers computing capabilities on different platforms like smartphones, tablets, PC, laptops, etc. |
| DDR3 RAM works on 1.50 V voltage | DDR3 RAM works on 1.20 V voltage. |
| DDR3 RAM has a 240-pin interface. | DDR4 RAM has a 288-pin interface. |
| This type of DDR RAM is backward compatible with the older RAM generations. | This type of DDR RAM is not backward compatible with the older generation’s RAM. |
| Decade-old demand for DDR3 RAM is waning. | The demand for DDR4 RAM is on a constant rise because of its implementation of emerging technologies. |
What are the advantages of DDR4 over DDR3?
Lower power
DDR4 modules are more energy-efficient, operating only at 1.2V compared with DDR3’s 1.5V or 1.35V. The reduced power consumption gives substantial power savings and allows operation at higher speeds without higher power and cooling requirements.
Higher module density
DIMM densities start at 2 GB, reaching up to 128 GB – a big leap from DDR3’s 512 MB to 32 GB capacities.
Faster data transfer speed
ATP’s latest DDR4 modules for embedded and industrial applications deliver high-speed data transfers up to 3200 MT/s. DDR4-3200, the latest industrial DDR4 offering from ATP, transfers data about 70% faster than DDR3-1866, one of the fastest DDR3 versions available, for a big boost in theoretical peak performance.
|
Item |
DDR3-1866 |
DDR4-3200 |
|---|---|---|
| I/O bus clock |
933 MHz |
1600 MHz |
| Data rate |
1866 MT/s |
3200 MT/s |
| Peak transfer rate |
14928 MB/s |
25600 MB/s |
Is 8GB of DDR4 actually better than 16GB of DDR3?
16 GB DDR3 was the most sensible choice for most people when the question was posed. The general answer for today is: “when choosing between more DRAM vs. DRAM that is slightly faster, pick more DRAM”.
Many great answers to this question. The detailed answer of which is faster is “it depends on which program you are running.”
But there’s more to take away at a high level. If we look at the performance of a computer with equal quantities of DDR3 or DDR4, across a range of programs, DDR4 and DDR3 are very close, maybe with DDR4 a few percent faster on average. DDR3 is faster in some cases. In a very small number of real programs, DDR4 gets you as much as 10%.
On the other hand, compare the performance of a program running on 16 GB of RAM versus 8 GB of RAM. If you need more than 8 GB, then the program will start paging, and execution could slow down by 4–100X. So the 16 GB machine could literally be 10,000% faster. In fact, the difference is so great you would have to quit the program because you could not bear to wait for it to finish. The 8 GB machine can effectively run fewer programs than the 16 GB machine! Another case is where you are using a lot of data (e.g. scrolling through pictures), in which case your extra DRAM will be used as a cache and can also speed things up by many multiples.
So if you have characterized your programs and the data they operate on very carefully, then 8 GB DDR4 might be the right solution, giving you up to 10% more performance. But if you don’t know exactly what you are running, more DDR3 means that you are less likely to encounter serious performance problems with your machine, at a small average cost in daily performance.
