▷ Memory ddr4 vs ddr3

The two largest speed pools for a PC are storage and RAM. More RAM improves PC performance, not only for the most important applications like games, but also for the most common applications like web browsers. DDR3 was a huge leap over its predecessor DDR2, and this comparison looks to see if that holds true for DDR4 as well. DDR4 vs DDR3.

DDR4 vs DDR3: the key differences

The DDR4 standard offers a higher module density, better reliability, higher transfer rates and lower voltage, which provides higher speed and better energy efficiency. It is also a standard designed with the future in mind; for example, it supports 3D stacking of dies with silicon vias (TSVs), allowing the module density to be increased by stacking up to 8 dies. But in practice, users may not experience a noticeable difference in performance when using the currently available DDR4 RAM modules.

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DDR4 supports low-power automatic auto-update (found in the documentation as LPASR), which has the standard function of updating memory content, which uses a temperature-based adaptive algorithm to prevent drift from the signal. The update modes of each module will also adjust each matrix independently, as the driver must support a precise optimization routine to also match which parts of memory are being used. This has power and stability implications for the long-term future of DDR4 design.

Module training when the system boots is also a key feature of DDR4. During the startup routine, the system must sweep through the reference voltages to find a maximum pass window for the selected speeds rather than simply applying the voltage in the options. The workout will go through the voltage reference in steps from 0.5% of the VDDQ (typically 1.2V) to 0.8% and the set tolerance of the module must be within 1.625%. Calibration errors are plausible at one step size (9.6 mV to 1.2V) but loss of gyration due to calibration error should also be considered. This is due to the greater involvement of losses due to margins and tolerances and ensures stable operation during use.

DDR4 operates at a lower voltage than DDR3. DDR4 runs at 1.2 volts, below 1.5. It doesn't sound like much, and it really isn't for your typical home PC. Most desktop systems will work somewhere in the 300W to 1200W range. The voltage difference for those numbers could represent a 15W savings over DDR3, not much for a home user. But for server farms and other large-scale computer architectures, where you could have hundreds of systems running thousands of DDR4 modules, that 15W difference adds up.

Another big difference DDR4 vs DDR3 is speed. DDR3 specifications started at 800 MT / s (or Millions of transfers per second) and some reached 2133. DDR4, meanwhile, starts at 2133 MHz. Increasing speed means an overall increase in bandwidth. Unfortunately, this also leads to an increase in latency, but the increased clock speed makes transfers faster, while maintaining overall latency comparable to DDR2 and DDR3. DDR3-1600 operated at a latency of CL11, which took 13.75 nanoseconds to initiate a read. DDR4-2133 is at CL15 and is reading at 14.06 nanoseconds, just a 2% increase.

DDR4 is not compatible with DDR3 motherboards because the physical design of the modules (DIMMs) for DDR4 and DDR3 is different. DDR3 modules use 240 pins and DDR4 DIMMs use 288 pins. Both DDR3 and DDR4 DIMMs are 133.35mm long, but the pins on DDR4 are closer (0.85mm) than DDR4 (1mm).

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They are also different in height and thickness: Increasing the height of DDR4 modules (31.25mm instead of DDR3's 30.35mm) makes signal routing easier, and increased thickness (1.2mm vs. 1). DDR3 mm) supports more signal layers. The notch position on DDR4 memory modules is also different from DDR3 modules. This prevents accidental insertion of the wrong type of memory because they are not backward compatible.

The DDR4 standard allows DIMMs of up to 64GB of capacity, compared to the maximum of 16GB DDR3 per DIMM. For most consumers, the choice will be simple because DDR4 is not backward compatible. If your motherboard was designed for DDR3, then that's what you can choose. Even if you are setting up a new PC, you will still choose based on the other components, the CPU and the motherboard, of the system.

This ends our article on DDR4 vs DDR3 memory, you can leave a comment if you have any questions.

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