The principle of operation, types and characteristics of memory
RAM is a chip used to store data of various kinds. There are many varieties of these devices, they produced a variety of companies. The best producers often have a Japanese origin.
What is it and why is it needed?
RAM (called RAM-memory) is a type of volatile chip used to store various information. Most often it is:
- the machine code currently running programs (or in standby);
- input and output data.
The exchange of data between the CPU and RAM is implemented in two ways:
- using ultrafast register of ALU;
- using a special cache (if present in design);
- directly (directly via the data bus).
The considered devices present a scheme built on semiconductors. All information stored in all kinds of electronic components, is still available only in the presence of electric current. As soon as the voltage is switched off completely, or momentarily open the power supply, all contained within the RAM is erased or destroyed. The alternative is the device type of ROM.
The types and amount of memory
Charge today can have a volume of several tens of gigabytes. Modern technical equipment allows to use it as quickly as possible. Most operating systems are equipped with the ability to interact with such devices. There is a proportional relationship between the RAM and cost. The greater the size, the more it is expensive. And Vice versa.
Also the device in question can have a different frequency. This parameter determines how quickly the interaction between RAM and other devices of the PC (CPU, data bus and video card). The higher the speed, the more operations will perform the PC per time unit.
The value of this characteristics also directly affects the cost of the device in question. Modern is the fastest modification can memorize 128 GB. It is manufactured by a company called Hynix and has the following performance characteristics:
- view of processes – 20 nanometer;
- bandwidth is 17 GB/s;
- frequency – 2133 MHz;
- interface I / o – 64-bit.
All modern RAM can be divided into two types:
More expensive to date is the chip static. Marked it as SDRAM. Dynamic is cheaper.
Hallmarks SDRAM-varieties are:
- binary and ternary digits stored in positive feedback;
- maintained a constant state without regeneration.
Also a distinctive feature of the RAM is having the opportunity to exercise the choice bits, which will be implemented recording any information.
The disadvantages include:
- a low recording density;
- the relatively high cost.
The device from the computer memory all kinds of kinds (SDRAM and DRAM) have external differences. They are the length of the contact part. Also has its difference form. The symbol of RAM is on the label is a sticker and is printed directly on the plate.
Today there are many different modifications of SDRAM. It is denoted as:
- DDR 2;
- DDR 3;
- DDR 4.
Another type of chip is referred to as DRAM. It is also fully volatile, access to bits of the records is carried out in an arbitrary manner. This type is widely used in most modern PCs. It is also used in those computer systems where high demands on the delay – performance DRAM much higher SDRAM.
Most often this type has the form factor DIMM type. The same design solution used for the manufacture of static schemas (SDRAM). Feature DIMM-execution is that there are contacts on both sides of the surface.
The parameters of the OP
The main criteria of selection circuits of this type are their operating parameters.
Should focus primarily on the following points:
They all depend on the type of specific model. For example, DDR 2 will perform various actions definitely faster than DDR 1 strap. As it has more outstanding performance.
The timings is the time delay of information between various components of the device. Types timings quite a lot, they all directly affect the performance. Small timings allow you to increase the speed of execution of different operations. There is one unpleasant proportional dependence – the higher the performance of the operational storage device, the more timings.
The way out of this situation is the increase of the operating voltage – the higher it is, the smaller the timings. The number of operations performed per unit time at the same time increases.
Frequency and speed
The higher the RAM bandwidth, the greater its speed. Frequency is a parameter determining the throughput of the channels through which data transmission to the CPU via the motherboard.
It is desirable that this characteristic coincides with the permissible speed of the motherboard.
For example, if the bar supports 1600 MHz, and the motherboard – no more than 1066 MHz, the communication speed between RAM and CPU will be limited by the motherboard. That is, the speed will not exceed 1066 MHz.
Performance depends on many factors. A very big impact on this parameter provides the number of used blocks. Dual channel RAM works much faster than single channel. The ability to support modes of multi-channeling is indicated on the label located on top of the Board.
These designations are as follows:
- Single (single);
- Dual (double);
- Triple (triple).
To determine which mode is optimal for your specific motherboard, you need to count the total number of slots for the connection, and to divide them into two. For example, if their 4, you need 2 identical strips from the same manufacturer. With parallel installation of Dual mode is activated.
The principle of operation and function
Implemented the functioning of the OP is quite simple, the writing or reading of data is carried out as follows:
- on the desired row is supplied electrical signal;
- is the opening of the transistor;
- the electric charge stored in the capacitor is supplied to the column you want.
Each column is connected to an extremely sensitive amplifier. He registers the flow of electrons that occurs in the case that the capacitor is discharged. Process is followed by the corresponding command. Thus, there is the implementation of the access to the various cells on the Board. There is one important caveat that should know. When the electrical impulse on any row, it opens all of its transistors. They are directly connected.
From this we can conclude that one line is the minimum amount of information that can be read when access. The main purpose of RAM is to store various kinds of temporary data that are required while a personal computer is turned on and functioning operating system. In RAM loaded with the most important executables, the CPU carries out their execution directly, just keeping the results of the operations.
Also, the cells stored:
- runtime libraries;
- key codes press on which it was made;
- the results of various mathematical operations.
Optionally everything that is in RAM, the CPU can save to your hard drive. And to do so in the form in which it is needed.
In stores you can find huge amount of RAM from different manufacturers. A large number of such products became available from Chinese companies.
By far the most productive and high-quality are the products of the following brands:
She is a compromise choice between quality and performance.
Table characteristics of RAM
RAM of the same species from different manufacturers has similar performance.
That is why the correct comparison, taking into account only the type:
2.5 v +/- 0.1 V
1.8 V +/- 0.1 V
1.5 V +/- 0.075 V
The number of blocks
all DQ signals
TSOP or Fly-by
Automatic calibration with ZQ
The presence of the temperature sensor
Comparison of performance and price
Performance of RAM depends on its value. To know how much is the DDR3, at the nearest computer store, you should also be familiar with the price of DDR 1. Comparing their performance parameters and price, and then testing, it’s easy to see this.
The most correct comparison RAM of the same species, but with different performance, depending on the frequency of work:
Speedwork, Aida 64, Memory Read, MB/s
In Aida 64 testing of all DDR 3 was performed on identical hardware:
- OS: Windows 8.1;
- CPU: i5-4670K;
- video card: GeForce GTX 780 Ti;
- motherboard: LGA1150, Intel Z87.
RAM is a very important part of PC, greatly affecting its performance. That is why its increase is recommended to install the planks with high frequency and small timings. This will give a big boost in computer performance, it is especially important for games and various professional programs.