What is DDR3 RAM? Design, Uses, Lifespan, Pros & Cons

July 15, 2020

In This Article

What is DDR3 RAM?

DDR3 RAM (Double Data Rate 3 Random Access Memory) is a type of computer memory that is used for temporary data storage and retrieval. DDR3 RAM is a newer and faster version of DDR2 RAM and provides increased bandwidth and speed for the computer system.

It operates at a clock speed of 800 MHz to 2133 MHz and has a data transfer rate of 800 MHz to 17,066 MHz. DDR3 RAM uses a lower voltage than its predecessor and is compatible with motherboards that support DDR3 technology.

DDR3 RAM is commonly used in modern desktops, laptops, and servers for faster processing and better overall performance.

KEY TAKEAWAYS

The DDR3 memory chips offer higher bus clock speed and capacity and consume less power than a DDR2 RAM.
The DDR3 chips used in the desktop computers come with 240 pins and those designed for the laptop computers come with 204 pins.
These memory chips are not forward or backward compatible because they differ in timing and signaling voltages.
If it is not overclocked excessively and if the voltage is within limits, a DDR3 RAM will last for several years.
DDR3 supports demanding tasks and applications and offers a higher prefetch buffer and less probability for damage. However, CAS latency, shorter clock cycles and its cost are few downsides.

Understanding DDR3 RAM

The official abbreviation of a DDR3 RAM is DDR3 SDRAM which stands for Double Data Rate 3 Synchronous Dynamic Random-Access Memory.

This SDRAM comes with a high bandwidth interface which is why it is called ‘Double Data Rate’ interface.

Released in 2007, this memory module is considered to be the successor of a normal DDR and DDR2 memory module.

Considering its design structure, features and year of release, a DRR3 RAM is also considered to be the predecessor of the latest memory chips, DDR4 and DDR5, which is yet to hit the market later this year.

The specialty of this specific memory chip is that it is not forward or backward compatible with any type of earlier memory chips.

This is because it differs from these memory chips in a few specific aspects such as in its:

Timings
Signaling voltages
Power usage and others.

This DRAM interface specification, however, is pretty similar in performance to the earlier types because the DRAM collections actually store the data in similar forms as the earlier memory module types.

This chip can transfer data at more than 8 times the speed of the internal memory arrangements of it.

This means that this memory chip will transfer data at double the speed of a DDR2 RAM.

It also means that this memory chip has a peak data rate and a higher bandwidth. Check out differences between DDR3 and DDR4 RAM.

The chip works in two different cycles for each data transfer. These cycles are in accordance with the quadrupled clock signal.

This means that if the DDR3 RAM is 64-bit wide, it can transfer data at a speed that is actually 64 times the speed of the memory clock for each memory module.

The transfer rate of this memory module is calculated by multiplying different factors such as:

The memory clock rate
Bus clock, which is 4
Data rate, which is 2 and
Number of bits it can transfer, which is ideally 64.

The result is then divided by 8, which is the transfer rate of data expressed in the number of bits in a byte.

Therefore, if a DDR3 RAM has a memory clock rate of 100 MHz, the data rate transfer will be calculated as: (100 x 4 x 2 x 64) / 8, which will come up to 6400 Mbps, double that of a DDR2 RAM.

As per the DDR3 standard, the capacity of the chip will be 16 gigabits or Gigabytes.

There will be 4 ranks of 64 bits DDR2 DIMM, implying that for each DIMM it is 16 gibibytes.

It is due to the hardware limitations in most of the older versions of the Intel CPUs, these do not support chips of more than 4 Gibits for the 8 Gibit DIMMs.

This issue was however remedied in 2013 with the inclusion of Ivy Bridge-E in the Intel CPUs.

On the other hand, all CPUs manufactured by AMD appropriately supported the entire specification of the 16 Gibit DDR3 DIMMs.

The design of the DIMM or Dual-Inline Memory Modules of the DDR3 RAM is also notable such as:

It has 240 pins which are not compatible with DDR2 RAM,
It has a key notch placed differently as compared to the DDR2 DIMM which prevents accidental interchange of the keys,
The notches are square on the sides as opposed to the rounded ones seen in a DDR2 memory chip, and
The SO-DIMMs of DDR3 chips come with 204 pins.

Due to these differences in features, manufacturers of CPUs have made a few noteworthy alterations in their microarchitecture.

For example, Intel has designed a specific SO-DIMM package for the Skylake microarchitecture called UniDIMM.

This feature enables the CPU to permit using either a DDR3 chip or a DDR4 memory module on the motherboard.

There is also a memory controller integrated in this memory chip which can work with any of these two memory modules.

The primary purpose of designing the UniDIMM by Intel is to help the CPU in its transition from one memory chip to another.

The CAS latency of the DDR3 chip is also numerically higher. This is because the cycles of the I/O bus clock are much shorter. It is for this reason that the difference between the DDR2 latency and a DDR3 RAM latency will be around 10 ns.

This CAS latency, denoted by ‘ns’ is measured by the following formula:

1000 × cycles or CL ÷ clock frequency in MHz = 2000 × CL ÷ transfer rate in MT per second.

The latest versions of DDR3 RAMs such as the DDR3 2000 comes with 9 ns latency which is in the form 9-9-9-28 and is compatible with the Intel Core i7, released at the same time as the DDR3 2000 in 2008.

Design Basics

DDR3 is an SDRAM used as the memory of a computer system and is available in two different form factors namely, DIMM and SO-DIMM.

Very much similar to the design of a DDR2 RAM, the DDR3 RAM has some significant differences from its counterpart which include:

Consuming 30% less power and
Transferring data at double speed.

The DDR3 memory module will also look similar to a standard DDR memory but the difference will be in the space between two sets of pins that separates one set from the other. These pins are ideally located at different locations at the bottom of each DDR3 memory module.

This alteration in the design structure of this memory module has a specific significance:

You will not be able to install this chip into a slot that is not compatible for using a DDR3 RAM, and
If you want to upgrade your system then you must look for the right type of motherboard with a slot that will allow you to fix this memory chip in your computer.

Since the DDR3 RAM can transfer data at a speed of 6400 megabytes per second, it prevents the common bottlenecks while processing large volumes of complex data.

This means that a computer that comes with DDR3 RAM will perform much better and faster than a computer with DDR2 RAM, considering that both have the same type of processor clock speeds.

Apart from facilitating in faster data transfer consuming much less power, the DDR3 RAM also comes with several other benefits simply due to its useful and innovative features, A few of its features include:

A bus clock speed within the range of 400 MHz and 1066 MHz
A wide range of size from 1 GB to 24 GB
The 240 pins in it, making it suitable for desktop computer and
For laptop computer compatibility, it has 204 pins.

However, these memory modules are not backward compatible with a DDR2 memory chip.

This is because you can install a DDR3 chip only onto a specific motherboard that has specific slots to support this memory chip.

Operating at 1.5 volts, the DDR3 consumes at least 30% less power as compared to the DDR2 RAM that functions at 1.8 volts. This low voltage indicates a higher battery life, apart from a significantly better performance of the computer system.

With further developments in design and features there are several other DDR3 RAM types available such as:

The DDR3 2400 that comes with a 9 to 12 cycle and 7.5 to 10 ns specifications and
The DDR3 3200 has 13 cycles and 8.125 ns latency.

These features also make the chip more energy efficient which depends on different factors such as:

Speed
Voltage
Usage type and more.

The features of the chip also help in its data transfer speed, which is denoted by DDR3-xxx and its increased bandwidth, denoted by PC3-xxxx. These indications also describe the DIMM assembly.

The bandwidth of the chip is the data transfer speed per second multiplied by 8. This is because the DDR3 memory module bus is 64 data bits wide where each byte is made of 8 bits.

Therefore, there are 8 bytes in each data transfer and that is why the data transfer speed is multiplied by eight.

This data transfer rate, expressed in MT per second is double the I/O bus clock, measured in megahertz. This is because the DDR3 RAM is a double data rate memory.

Uses of DDR3 RAM

DDR3 RAM was used on almost everything after its launch in 2007. This memory chip ruled the computer world till 2017 when the modern computers came with a DDR4 RAM only and a 6^th Generation Skylake CPU, switching from the Intel platform. However, till 2017 the DDR3 RAM was extensively used in:

Intel LGA1366
6^th and 7^th generation core Intel LGA1151
AMD AM3
AM3+ of AMD
FM1
FM2 and
FM2+.

On and from 2017, the 8^th and 9^th Generation Core CPU and the AMD Ryzen processor typically used a DDR4 RAM.

Lifespan of DDR3 RAM

Ideally, the DDR3 RAM can be expected to run for years. There is more life in it. In fact, you can expect it to be used and continue working even after the DDR5 RAM is out in the market. Since DDR5 is not backward compatible it will need a new motherboard.

Therefore, if you do not want to spend on any upgrade right now, do not fret because your DDR3 RAM is expected to run for several years. Unless it is slowing your system down, you should not worry about replacing your DDR3 RAM.

Ideally, most of the memory chips come with a lifetime warranty, and DDR3 is no exception. Therefore, there is no need to replace it if you:

Do not really want to
Do not see any problems with overclocking and
Have high speed memory.

However, make sure that you do not overvolt or overclock it. If you really have to, then make sure that you use a proper and more effective cooling system so that the RAM does not start to flake out due to overheating in a very short time.

The Pros

1. Less power

The DDR3 RAM will consume a lot less power as compared to the DDR2 RAM. This is primarily due to the variance in supply voltages.

The DDR3 RAM has a range of 1.35 volts to 1.5 volts and the DDR2 RAM will have a range of 1.8 volts to 1.9 volts.

The dual gate transistors used in a few particular DDR3 RAMs by the manufacturers reduce the chances of leakage of current from them as well.

2. Stability and performance

The stable 1.5 supply voltage is best suited for the ninety-nanometer fabrication technology of the original DDR3 RAMs.

This enhances the performance and also ensures more stability. This is good to use in servers as well as in different devices used for complex missions.

3. Probability of damage

The possibilities of permanent damage for this specific RAM is far too less because, according to a statement of JEDEC, this memory device can endure up to 1.80 volts.

However, it may not perform properly when the voltage supply is that high.

4. Prefetch buffer

The 8 burst deep prefetch buffer of this RAM is double that of a DDR2 RAM and four times that of any normal DDR RAM.

This enhances the transfer speed of this RAM.

5. Higher transfer speed

The DDR3 RAM can transfer data at a much faster rate due to its features and technology used. When compared, the data transfer rate of a DDR3 RAM is 800 to 2133 MT per second.

During the process, it uses both rising and falling edges of the 400 to 1066 MHz I/O clock. This is exactly double the data transfer speed of a DDR2 RAM and four times that of an average DDR RAM.

6. High bandwidth

The bandwidth capacity of the DDR3 RAM is much higher as compared to other DDR RAMs.

This means that the RAM will perform better and will produce better results even when it is working at a low voltage and transferring data at the rate of 1500 megabit per second.

7. Suits demanding applications

This reliable memory will support running more demanding and complex applications on the computer such as a high-end video game.

8. Temperature

The operating temperature of this memory chip is also far cooler than other DDR RAMs.

The Cons

9. Cost

As compared with DDR2 RAM, you may find that the DDR3 RAM is slightly on the higher side.

10. CAS latency

The CAS latency of DDR3 RAM is also typically higher.

In comparison with JEDEC DDR2 RAM which has a standard latency of 5-5-5-15, the new JEDEC DDR3 1066 RAM comes with a 7-7-7-20 CAS latency.

It will take some time for it to fall below JEDEC latencies.

11. Clock cycles

The clock cycles of a DDR3 RAM is much shorter as compared to its counterparts which also is the cause for its higher CAS latency.

12. Motherboard

You will need to install a separate and far too expensive motherboard to use the DDR3 RAM because the slots in any standard motherboard will not support this memory module.

13. Performance

Overall, there will be only about a 5% increase on an average in the performance of the system when you use a DDR3 RAM.

However, it is not usable in XBOX 360 as most people believe. This is because this game uses a GDDR3 memory.

Summary

DDR3 RAM, or Double Data Rate 3 Random Access Memory, is a type of computer memory that provides increased bandwidth and speed for a computer system.

It operates at a clock speed of 800 MHz to 2133 MHz and has a data transfer rate of 800 MHz to 17,066 MHz.