DDR3 low profile. Dictionary of Terms: RAM

RAM - One of the most important components of the system, from which the performance of the computer directly depends. In the catalog, you can choose and buy the RAST memory of the appropriate type of 1 to 32 GB, single planks, as well as Kit memory modules 2 and 4 planks included with the same characteristics selected for work in a pair (two-channel mode). The use of a two-channel mode leads to a significant increase in bandwidth, and, consequently, to an increase in the speed of the applications. For compact systems, low-profile memory modules are provided, differing from standard in height, but not by performance. While for outdated platforms are presented regular and server memory modules REGISTERED DDR, DDR2, REGISTERED DDR2 and DDR2 FB-DIMM. Available prices for the RAM of these standards make a choice obvious when searching for replacing faulty memory or expand the existing total memory in the system.

To date, the most common type of memory for desktop PCs on intel database and AMD is the DDR3 RAM. However, with reduced voltage (LV DDR3) is not supported by all motherboards and processors.

For the very modern processors Suitable. It is distinguished by double-to-3.2 Gb / s maximum data transfer rate, increased to 4266 MHz maximum frequency and unsurpassed stability of work. The enlarged number of contacts makes DDR4 modules incompatible with old slots.

The higher the clock frequency, the more operations are performed per unit of time, which allows you to more steadily and quickly computer games and other applications. Prices for RAM with high clock frequency, it goes without saying above. But before you buy memory, pay attention to what the maximum frequency is specified in the processor description. Use of memory with frequencies more stated values \u200b\u200bof noticeable productivity growth will not give.

If you are collecting gaming computer, powerful workstation or planning to engage all the components of the system, then you should buy a gaming memory, which differs from a standard high frequency, high voltage and, if possible, smaller delays. Game memory prices are not the lowest, but in this case the performance of the system will be higher than when using standard memory schedules. The decoration of any gamers will be backlit. White or multicolor illumination does not affect performance indicators, however, it looks very stylish and relevant to the PC of this class.

Fast memory modules are distinguished by the presence of profiles that expand the capabilities of SPD. The most popular currently refers to the so-called. XMP support allows you to overclock the DDR3 and DDR4 memory and thereby achieve even higher performance and improve game functions without complex voltage changes and memory frequency.

ATTENTION! This article is not a call to action, but is solely an informational character.

Is no less an important part Computer. Despite the fact that this item has small sizesFrom it largely depends on the speed of your computer. It has basic characteristics, such as volume and frequency.

RAM volume

The essence of the action of RAM can be understood from its name: this is the memory that must work promptly. For example, you have hDDwhere some data is stored. You run the application to which data from hard disk Needed for work. If the computer will constantly apply for the data you need to the hard disk, it will take quite a lot of time - therefore it loads these data into RAM and can turn to them much faster, "here and now." It follows that the larger the amount of RAM, the better.

As in the case of other components of the computer, the amount of RAM should be chosen based on the purposes. If you are working only with undemanding office applications, then a large amount of RAM will simply simply stand up, and this is an excessive overpayment of money, at the same time users who work in more serious programs, such as gamers, operational memory is required. However, you should adhere to the optimal option and get the memory of at least four gigabytes - this volume will be quite enough for comfortable work. home ComputerEven for entertainment in games.

RAM frequency

Such a concept as a frequency in RAM is responsible for its speed. That is, at what speed the computer will be able to take and download the necessary data into this memory. It also operates the principle "the more, the better."

There are several types of RAM. This is DDR, DDR2 and DDR3. Each of them differs in that it has a maximum frequency more than the previous type. The optimal option will be the frequency of 1200 to 1600 MHz. If the budget is limited, then it is worth preferring RAM with a lower frequency, but not less than 1200 MHz. This is due to the fact that the price of such memory will be smaller, and the difference in performance the usual user will not even notice.

Important momentsto pay attention to

The most important thing is that the details in our computer are not only fast, but also fully compatible. Therefore, it is necessary to ensure that the type of memory, its volume and frequency coincide with the same parameters on the motherboard. If these parameters are incompatible, it either will not work at all, or will not work as we would like. For example, if the maximum allowable amount of RAM on the Motherboard 8 gigabytes, and the "Planck" will be inserted by RAM to 16 gigabytes, the memory is involved only half, that is, extra money has been replete.

So, there are ordinary and low-profile "strips." Low profile have smaller sizes that are suitable for small buildings, but insert a "bar" normal size This case will already be difficult. In order not to make a mistake, you can take low-profile "strips" anyway, as they are suitable for any body, and their performance is no different. Otherwise, you must ensure that the dimensions of the RAM are approaching your corpus and motherboard.

This is a module whose function is to store data and providing them with a device or program - in fact this is an intermediary between the processor and disk drives. RAM is an energy-dependent device, i.e. It can only work while the power is supplied to it, when the disabling all the data is lost. We will understand in more detail in the characteristics of this. the most important device, without which your PC, smartphone, laptop or tablet will be a conventional chest iron.

Types of RAM

RAM have several types of drawn characteristics and architecture.

- Synchronous dynamic memory with arbitrary access. It used to be quite popular and was used in almost all computers, due to the presence of synchronization with the system generator, which, in turn, allowed the controller to determine the time when the data is ready. As a result, the time of waiting cycles in connection with the availability of data on each timer is significantly reduced. Today is ousted more modern types Memory.

- This is a dynamic synchronized memory, it is based on the principle of accidental access and the double data exchange rate. Such a module has a number of positive characteristics relative to the SDRAM, the most important of which is 2 operations for 1 cycle of the system generator, that is, with a constant frequency bandwidth At the peak increases by 2 times.

- This is the next development, it works in the same way as in RAM type DDR, a distinctive feature of this model consists in doubled by volume of data sample on the tact (4 bits instead of 2x). In addition, the second generation has become more energy efficient, the heat dissipation decreased, and the frequency rose.

- New generation RAM, the most important distinctive feature from DDR2 - grew frequencies and reduced energy consumption. Also completely changed the design of the keys (special slots for accurate entry into the slot).

There are modifications DDR3, characterized by even less power consumption - DDR3L and LPDDR3 (the voltage at the first model is reduced to 1.35 V, and in the second to 1.2 V, whereas simple DDR3 it is 1.5V).

DDR4 SDRAM - the newest generation random access memory. It is characterized by grew up to 3.2 Gbps / at the rate of data exchange, increased to 4266 MHz frequency and significantly improved stability.

Rimm. (RDRAM, Rambus Dram) - Memory based on the same principles as DDR, but with an increased level of clock frequency, which has been achieved due to the smaller tire bit. Also, when addressing the cell number of the line and column is indulge at the same time.

The cost of Rimm was much higher, and the performance only a little exceeded DDR, as a result, the RAM of this type has long been in the market for a long time.

Choose the type of RAM not only on the basis of the potential and characteristics of your motherboard, but also considering compatibility with other components of the system.

Options for the physical location of chips (packaging)

Memory chips installed on the RAM modules are located either on the one hand (one-sided location) or two (two-sided). In the last variant, the modules are obtained quite thick, which does not allow them to install them on separate PCs.

Form factor is

Specially designed standard in which the dimensions of the RAM module are described, the total number and location of contacts. There are several types of form factors:

SIMM. (Single in Line Memory Module) - 30 or 72 bilateral contacts;

Rimm. - Corporate Form Factor Rimm Module (RDRAM). 184, 168 or 242 contacts;

Dimm. (Dual in Line Memory Module) - 168, 184, 200 or 240 independent, located on both sides of the module, contact pads.

FB-Dimm. FULLY BUFFERED DIMM) - exclusively server modules. Identified by DIMM form factor with 240 contacts, but use only 96, due to the serial interface. Thanks to the AMB (Advanced Memory Buffer), high-speed buffering and conversion of all signals, including addressing, is provided on each AMB microcircuit module. Also significantly improved performance and scalability. Compatible only with similar fully buffered memory.

LrDimm. Load Reduced Dual In-Line Memory Modules) - exclusively server modules. Equipped with the IMB buffer (Isolation Memory Buffer), which reduces the load on the memory bus. Used to accelerate the work of large amounts of memory.

Sodimm. (Small Outline Dual In-Line Memory Module) - subspecies of DIMM with smaller sizes for installation in portable devicesmainly laptops. 144 and 200 contacts, in a rarer variant - 72 and 168.

Microdimm. (Micro Dual In-Line Memory Module) - even reduced sodimm. Usually have 60 contacts. Possible contacts of contacts - 144 SDRAM, 172 DDR and 214 DDR2.

A separate mention deserves low profile memory - created specifically for low server enclosures modules with a smaller, compared with standard, height.

Form factor is the main parameter of the RAM compatibility motherboardSince when it missed, the memory module is not easy to insert into the slot.

What is SPD?

Each DIMM form factor bar has a small SPD chip (Serial Presence Detect), in which data is sewn about the parameters of physical chips. This information It has a critical value for uninterrupted operation and the BIOS is read at the test stage to optimize the access parameters to RAM.

Memory module wounds and their number

A memory block of a 64 bit width (72 for modules with ECC) formed by N physical chips. Each module can have from 1 to 4 wounds, and the motherboard has its own limit on the number of rings. Explain - if no more than 8 wounds can be installed on the motherboard, this means that the total number of RAM modules may not exceed 8, for example, in this case - 8 peer-eyed or 4 double-one. In independence, there were still free slots left whether there were no additional modules with an exhaust limit of the wounds.

Determine the rack for a specific RAM is quite simple. W. kingston companies The number of rings is determined by one of the 3rd letters in the center of the marking list: S is peernagova, D - Drochrangovaya, Q is a four-grand. For example:

KVR1333D3L S.4R9S / 4GEC.
KVR1333D3L D.4R9S / 8GEC.
KVR1333D3L Q.8R9S / 8GEC.

Other manufacturers indicate this parameter as, for example, 2RX8, which means:

2R - two-colored module

x8 - Data bus width on each chip

those. The 2RX8 module without ECC has 16 physical chips (64x2 / 8).

Timing and latency

Performing any operation with a memory chip occurs for a certain number of system bus cyters. Required for recording and reading data number of clocks and there are timings.

Latency, if briefly, delayed access to memory pages is also measured in the number of cycles and is written by the 3rd numeric parameters: Cas Latency, Ras to Cas Delay, Ras Precharge Time. Sometimes the fourth digit is added - "DRAM CYCLE TIME TRAS / TRC", which characterizes the overall speed of the entire memory chip.

Cas Latency or Cas (CL) - Waiting from the moment when the data was requested by the processor and before the start of their reading with RAM. One of the most important characteristics of the determining speed of RAM. Little Cl speaks about high speed RAM.

Ras to Cas Delay (TRCD) - a delay between the transmission of the RAS signal (Row Address Strobe) and Cas (Column Address Strobe), which is necessary for a clear separation of these signals to the memory controller. Simply put, the data reader includes a string number and memory page column and these signals must be distinct, otherwise multiple data errors will occur.

Ras Precharge Time. (TRP) - determines the delay time between deactivation current line data and activation of the new one. In other words, the interval, later, the controller can again serve RAS and CAS signals.

Clock frequency, data frequency (Data Rate)

Data frequency (otherwise - data rate) is the maximum possible number of data cycles per second. It is measured in gigatransfers (GT / S) or Megatransprase (MT / S).

The clock frequency determines the maximum frequency of the system generator. It should be remembered that DDR is decrypted as Double Data Rate, which means a double-cycle data frequency relative to the clock. For example, for the DDD2-800 module, the clock frequency will be 400.

Bandwidth (peak data transfer rate)

The simplified version is calculated as the frequency of the system bus multiplied by the amount of data transmitted per clock.

The peak speed is the product of the frequency and bittenness of the tire on the number of memory channels (h × p × k). The memory module indicates, for example, PC3200, which obviously means - the peak data transfer rate for this module is 3200 MB / s.

For optimal system operation, the total value of the memory schedule should not exceed the PS of the processor bus, the exception is the two-channel mode when the planks will occupy the bus in turn.

What is the support of the ESS (Error Correct Code)

ECC support memory allows you to find and correct spontaneous errors during data transfer. Physically ECC is executed in the form of an additional 8-bit memory chip for every 8 basic and is significantly improved "parity control". The essence of this technology is to track one arbitrarily changed in the process of recording / reading a 64-bit batting machine with its subsequent correction.

Buffered (register) memory

It is characterized by the presence of special registers (buffers) on the RAM module processing control signals and addressing from the controller. Despite the additional tact of delays arising through the buffer, register memory is nevertheless widely used in professional systems due to the reduced load on the synchronization system and significantly increased reliability.

It must be remembered that buffered and nebuphrairized memory are incompatible and cannot work in one device.

Hello, dear blog readers Website. Today I would like to tell about the operational memory of the computer. It (memory) is not yet rarely called RAM - an operational storage device, or RAM - that translated from Bourgeoisky means "memory with arbitrary access", that is, memory is not only reading, but also to record information.

Slightly above, I mentioned the word "device", although in fact the rapid memory is not called a full-fledged device somehow the language does not rotate. In essence, RAM is one or, which is most often found - several rectangular planks. Many, having come to the computer store, are perplexed, as can be given for some kind of garbage 1000-2000 rubles! (Depending on the volume and type of memory, of course). And the bar in 2000 rubles. Not far, believe me, is even more expensive - just 5-6.

The fact is that the computer's operational memory is needed to store temporal information, i.e. until the computer is turned off. Under the temporary information is meant OS ( operating system), everything open programs and services and more things every garbage. It turns out that the larger the amount of RAM, the more programs can be opened at the same time, the faster the OS itself will work, as it will disappear to constantly load the OS files with. The benefits of course a lot, but the main of them are still - speed \u200b\u200band multitasking. In a situation with games, there is nothing to talk about, everything is simple, the more - the better. But I think 16 GB for games will be still a bit too much.

In 2006-2007, even 1 GB of RAM was "on board" even 1 GB. And although this volume was enough for most everyday tasks, it was felt that the system slows down, and in the games it was more noticeable. In fact, the volume is not the only one important characteristic RAM, there are two more: the type of memory and its frequency. I propose to talk about it in more detail.

But before, let's see with you, where the RAM is located.

As you can see, the RAM strips are attached to using special connectors, these connectors (slots) are only suitable for connecting the computer's RAM, no other devices to connect can be connected, as in the case of (where the connection interface serves pCI-E slot X16, to which other devices can be connected in addition to the video card).

As you understand, not all RAM are similar to each other. I propose to see what they may differ from each other. The first difference can be noted, just looking at the memory. I am talking about the height of the memory plank itself. Yes, quite recently to all familiar ordinary memory Added "low-profile" its version, here Look:

This type of memory will be convenient for installation, first of all, if the space in system block strongly limited, although initially this species Memory was used to install in server enclosures, due to the horizontal location and the low height of the latter.

So, as mentioned above, the volume is not the most important parameter that is characterized by the operational memory of the computer. With that if there is a 4 GB plank on the computer on 4 GB, but the type of this memory will be outdated, or the operating frequency is small.

What is it for the type of such, can you ask? Answer there are two types of RAMwhich differ from each other in itself the design of the player itself and the speed of its work (performance). Both of these types of memory are called DDR2 and DDR3, respectively.

At the time of writing the article, DDR2 is almost extruded from the market with its descendant - DDR3, due to the fact that the power consumption of DDR3 memory decreased by different estimates by 15%, in comparison with DDR2. And the DDR3 has a much greater bandwidth and steadily operates at a frequency up to 1600 MHz. Please note that these two types of memory are not compatible with each other, and all because there are differences even in the connectors themselves for mounting the memory.

On the images above, it is clearly visible to the cause of incompatibility, namely a small deepening in the rates of RAM, as well as a small sex in the memory slots on the motherboard. All this will not allow to accidentally put one type of memory into the computer instead of another, such a "fool protection". By the way, all that was stated above in the text, does not describe all the differences between the DDR2 and DDR3 memory, but the purpose of this post was not at all. I will only say that there will be other articles regarding the "RAM MEMORY". Perhaps this is all what I would like to tell here. See you!

The type of RAM, which defines the main characteristics of the memory and the internal structure. Today there are five main types of RAM: SDRAM, DDR SDRAM, DDR2 SDRAM, DDR3 SDRAM, RIMM.
SDRAM - synchronous dynamic memory that has random access. Pluses Compared to higher generation memory: Synchronization with a system generator, this makes it possible to control the memory to know a specific data availability time, with this innovation time delays in the process of waiting cycles are reduced due to the fact that the data is free for available during each tact timer. Previously, the SDRAM was actively used in computers, however, the DDR and DDR2 are currently extruded.
DDR SDRAM is a synchronous dynamic memory that has random access and characterized by a double information transfer rate. Pluses DDR SDRAM in front of SDRAM: For one system of the system generator, two operations with information can be carried out, which increases twice the peak bandwidth when working at the same frequency.
DDR2 SDRAM - Next for DDR generation of memory. The principle of work is similar to what is applied in DDR. Difference: It is possible to sample for one time of the 4-bit data (for DDR there is a 2-bit sample), an operating frequency is increased, the power consumption of memory modules is reduced, the heat dissipation is reduced.
DDR3 SDRAM is the next DDR2 SDRAM memory generation, the same "frequency doubling" technology applies. The main difference from DDR2: the ability to work at a greater frequency. DDR3 modules have 240 contact pads, but they are incompatible with old slots, as other orienting slots are applied ("keys").
Rimm (Rambus Dram, RDRAM) is a synchronous dynamic memory developed by Rambus. The main differences from DDR memory: an increase in the clock frequency by reducing the battery of the tire, simultaneously transmitting when contacting the memory of the column number and cell strings. RDRAM is much more expensive than DDR, and with similar performance, it led to the fact that this type Memory almost completely left the market.
When defined with the memory type, focus primarily on the capabilities of your computer's motherboard, as well as its compatibility with different memory modules.

Form factor
Standard Module RAM. Form factor (standard) Defines the dimensions of the memory module, as well as the number of contacts and their location. There are several absolutely incompatible memory standards: SIMM, DIMM, FB-DIMM, SODIMM, MICRODIMM, RIMM.
SIMM - 72 or 30 contacts are often located on the memory modules of this standard, each of these contacts is equipped with an output to the two sides of the memory card.
DIMM - DIMM standard memory modules, usually they have 240, 200, 184 or 168 independent contact sites, contact pads are placed on two sides of the memory card.
DDR2 FB-DIMM - This standard memory modules are used in servers. Mechanically, they are similar to DIMM 240-PIN Memory Modules, but are completely incompatible with conventional non-buffered memory modules REGISTERED DDR2 DIMM and DDR2 DIMM.
Sodimm is a compact version of the DIMM, usually used in Tablet PC and laptops. Most often has 72, 144, 168, 200 contacts.
Microdimm is one of the DIMM options for subnotebooks and laptops. The dimensions are less than Sodimm, characterized by the presence of 60 contact sites.
Rimm is a standard for RIMM memory modules (RDRAM), characterized by the presence of 184, 168 or 242 contacts.
RAM and standard module standard that supports motherboardmust match.

Volume of one module
from 0.03125 to 128 GB
The amount of memory that has one module. The total amount of system memory can be calculated by creating the memory volumes of all installed modules. For comfortable work in office programs and the Internet, there will be enough 512 MB. For normal operation with office applications, as well as graphic editors Enough 1 GB (1024 MB) RAM. Work in difficult graphic programs And playing computer games will allow 2 GB (2048 MB) system memory.

Number of modules
from 1 to 16
The number of memory modules sold in the set. Not only single planks are found on sale, but also kits, in the kit there may be two modules, four, six, eight, they all have identical characteristics and are selected to work in two-channel mode (pair). The use of such a two-channel mode allows you to achieve a tangible increase in bandwidth, and, as a result, increasing the speed of applications. It must be said that the fact that you bought two modules of one manufacturer, having the same characteristics, does not mean what they can work in two-channel mode. For this reason, if your computer's motherboard is capable of supporting a two-channel memory mode, then you should pay your attention to sets consisting of several modules, if for you, of course, high speed of graphic and game applications is important.

Number of contacts
from 144 to 288
Number of contact pads located on the memory module. The number of contacts on the module should coincide with the number of contacts in the slot for the RAM located on the motherboard. It must be remembered that besides the same number of contacts, the "keys" ("keys" call cutouts on the module are also obliged to coincide, they exclude the possibility of incorrect installation).

Number of ranks
from 1 to 8
The number of memory areas (ranks) of the RAM module. The wound is called a memory area that is formed by several chips or all memory module chips and has a width of 64 bits. RAM module, depending on the design, can have one, two or four wound. The server motherboards manufactured today are characterized by the presence of a limit on the total number of memory ranks, for example, if the maximum eight wounds can be installed and four double-colored modules are already installed, then install additional modules in free slots will not succeed. Their installation will cause the limit exceeding. That is why one-eyed modules are more expensive than two- and four-party.

Clock frequency
from 66 to 4800 MHz
The smallest frequency of the system generator, it occurs on it to synchronize the processes of receiving and transmitting information. For DDR, DDR2 and DDR3 memory, the double value of the clock frequency is indicated (two data transactions are carried out in one clock). The clock frequency is higher, the greater the number of operations per unit of time can be performed, it allows computer games and other applications to work more stable and faster. With all the other identical characteristics, the memory having a greater frequency is more expensive.

Bandwidth
from 1600 to 38400 MB / s
The bandwidth of the memory module is called the amount of information received or transmitted in one second. This parameter is directly dependent on the clock memory frequency. The bandwidth of the memory module is calculated by multiplying the bus width to the clock frequency. The bandwidth is greater, the greater the speed of memory, the greater the price of the module (if the remaining characteristics coincide).

ECC support
ECC support (Error Checking and Correction) Algorithm, which makes it possible and detect, and correct the error data randomly in the process (no more than one bit in the Bath). Error Checking and Correction is capable of supporting almost all server boards, as well as some motherboards for workstations. Memory modules with ECC cost more than those that do not support this algorithm.

Buffered (REGISTERED)
The presence of buffer (special registers) on the memory module, the special registers can quickly save the received data, reduce the load on the synchronization system, thereby freeing the memory controller. The presence of special registers between memory chips and the controller leads to the appearance of an additional delay equal to one tact, when performing operations, thus, higher reliability occurs due to a minor reduction in speed. Memory modules equipped with registers are characterized by a high cost, they are used mainly in servers. It should be remembered that incompatible nebuperized and buffered memory, which means that their simultaneous use in one system is impossible.

Low Profile)
The memory module that is characterized by a smaller height (compared with the standard size). This size allows it to be installed in low server enclosures.

Radiator
The presence of special plates of metal fixed on microcircuits, these plates are designed to improve heat transfer. Radiators are usually installed on memory modules that serve to work at high frequency.

XMP support
XMP (Extreme Memory Profiles) - profile containing data on the extended and non-standard features of the RAM module. Affordable BIOS Computer On the initial period of the download, switching to overclocking mode, without setting up all manual delays.

Timing

from 2 to 22
CAS Latency, CAS - the number of clocks since the data request before reading them from the memory module. CAS Latency, CAS is the most important characteristic of the memory module, it will determine the speed of memory. With a decrease in the number Cl, memory is accelerated.

tRCD.
from 2 to 26
Ras to Cas Delay is a delay between signals that define the column address and the address of the string.

tRP.
from 2 to 26
ROW PRECHARGE DELAY. This parameter determines the period of charge accumulation, the RAS signal recharge (re-issuance time), i.e. That time, after which the memory controller can again give an initialization signal of the address of the string.

tras.
from 5 to 52
ACTIVATE TO PRECHARGE DELAY is the smallest number of cycles between the RAS (Activation Team) and Precharge (command of recharging) or the closure of the same memory bank.

Additional Information

Supply voltage
from 1.2 to 3.3 in
The value of the voltage required for powering the module is required. All modules are designed for some specific voltage, so when choosing this item, make sure if your motherboard supports the required voltage.

Chips

Manufacturer
Manufacturer firm installed on the microcircuit module. Often the manufacturers of memory modules are used to produce their products of third-party chips.

number
from 1 to 184
The number of chips memory mounted on one memory module. To be chips can from either side and on both sides of the board.

Packaging
Method of location on the memory module of chips. Modules are produced with one-sided and double-sided packaging. If the microcircuits are located on both sides, the modules have a greater thickness, which prevents them in installing them in some systems.