How to choose RAM?
Replacing the RAM - a decent tuningold good PC. With RAM, you can increase the speed, performance and memory of your computer. But you need to replace the device with the mind: you can not just buy RAM. It must match the processor and the motherboard of the computer. Therefore, in the question of what kind of operational memory to choose, experts recommend referring to the characteristics of these components.
In order to determine which processor supports the motherboard, and what memory it needs, you should:
- Look at the site of the motherboard manufacturer.
- Find your model there by alphanumeric marking.
- Investigate the manual for supported processors and a list of those memory modules that manufacturers recommend for them.
So, what are the most important criteria for choosing RAM?
Despite the fact that the IT market is veryquickly improving, each time throwing on the court of consumers much more interesting models, we will tell you about the main types of memory that are dominant today:
- Memory module DDR 3rd generation or DDR3 (clock speeds 2,400 megahertz). The energy consumption and heat dissipation of this model is reduced by 40%.
- DDR2 memory module.
- Memory module DDR1.
All these modules are completely incompatible betweenand by electrical and physical parameters. It is for this reason, even with a selection error, you can not insert into the PC that bar that does not fit.
Form factor is called the standard, which specifies the dimensions of the device or, more simply, the type of construction of the bar. There are two:
- DIMM. Used for stationary computers and assumes that contacts are on both sides
- SO-DIMM. Applicable for laptops
Visually, their sizes differ almost twice (SO-DIMM is less).
Bus frequency and data rate (throughput)
These parameters are considered basic. They characterize the performance of "RAM" and give the answer in the end, how to choose RAM.
- The bus frequency indicates its ability to transmit data in a single unit of time. The higher this indicator, the more information you can "merge".
- The memory bandwidth determines the frequency that transmits data, the bus bit and the number of memory channels.
Both parameters are directly proportionaladdiction. So, for example, if the bus frequency is 1333 MHz, then its bandwidth will be 10,600 MB / sec, and the RAM will display the inscription: DDR3 1333 PC-10600.
How to choose the RAM, based on the bus frequency:
First of all, start from the possibilitiessystem. Ideally, if the bus frequency coincides with the frequency of the motherboard / processor. For example, if the DDR3-1800 module is purchased and the connector supports a maximum of DDR3-1600, the RAM will only work at the connector frequency of 1600 MHz. Moreover, in this scenario, failures in the operation of the entire system are possible. So to solve this problem it is better to buy the "RAM" DDR3-1600 or DDR3-1333.
Modes of work of memory
In modern PC modes of RAM supportmotherboards. It is in such modes that the speed of operation will be most effective. So, for maximum computer speed, consider both the modes of operation of the modules and their correct installation.
There are several types of memory modes:
- Single-channel (asymmetrical). It turns on when one RAM module is installed in the PC or in the case when all the modules are different in terms of memory, manufacturer or frequency of operation. At the same time, the memory itself does not matter, and to which connector it is installed. All RAM will start running at the slowest speed of the devices on the PC.
- Two-channel (balanced). In two channels, modules with the same volume of "RAM" are installed. Thus, the maximum data transfer rate is actually doubled. It is most common in practice.
- Three-channel. It assumes that each of the three available channels has the same amount of memory. All modules are sorted by speed and volume.
But professionals point out that often such a regime is less productive than a two-channel one.
- Flexible mode. It makes it possible to increase the performance of RAM in case two modules of different capacity are installed, but of the same frequency.
Memory size or size
It is believed that the amount of memory is almost the main characteristic of the module. It is assumed that the more it is, the better for the PC. But this is not always the case, although it occurs in practice.
Specialists also claim that the volume from 6 GB is quite reasonable, especially in those cases when the disk subsystem is weak.
Or temporary delay, latency of RAM. It is indicated as a sequence of several digits, for example, 3-3-3. They designate successive parameters:
- CAS Latency;
- time of full access (RAS to CAS Delay);
- RAS Precharge Time.
The lower the value of the timings, the faster RAM operates. They are measured in nanoseconds (ns) and take values from 2 to 9.
Sometimes a single digit is given in the characteristics. It means the first parameter - the time of the working cycle. The rest will be either equal to him, or more. So do not trust the marketing move.
When choosing memory, you should focus on the least timings. In the case of adding an additional module to the PC, the CL of the new memory must match the timings set.