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Functions of RAM

Definition:

Random Access Memory (RAM) provides space for your computer to read and write data to be accessed by the CPU (central processing unit). When people refer to a computer’s memory, they usually mean its RAM.

If you add more RAM to your computer, you reduce the number of times your CPU must read data from your hard disk. This usually allows your computer to work considerably faster, as RAM is many times faster than a hard disk.

RAM is volatile, so data stored in RAM stays there only as long as your computer is running. As soon as you turn the computer off, the data stored in RAM disappears.

When you turn your computer on again, your computer’s boot firmware (called BIOS on a PC) uses instructions stored semi-permanently in ROM chips to read your operating system and related files from the disk and load them back into RAM.

*****Ram is a electrronic scratch pad inside a computer.Ram is volatile meaning that it loses data when the computer shuts down or in case of power failure.Therefore RAM needs constant power supply to holds its data.

Example :

SDR, DDR, DDR2, and DDR3 RAM

Several types of RAM are used in modern computers. Before 2002, most computers used single data rate (SDR) RAM. Most computers made since then use either double data rate (DDR), DDR2, or DDR3 RAM. DDR2 is able to achieve faster transfer rates to prevent limitation of your CPU’s performance, and DDR3 technology takes these advancements even further.

Note that these RAM technologies are not interchangeable. One type of RAM will not function if installed with another type, and physical differences in the RAM modules prevent them from even being inserted in the same computer.

Functions of RAM :

RAM stores information for actively running programs so that data can be accessed and used rapidly. Contrast it to the hard drive where it has to physically write and read every bit of information, which would be far too slow to use for RAM.

In a nutshell, RAM is defined as Random Access Memory, which means that any byte or section of the memory can be accessed at any given time, verus say a tape drive which is sequential access memory since it must scroll to arrive at a section of the tape.

RAM functions using transistors. Currently the most common RAM is SDRAM or DDR RAM, DDR Ram is based off of SDRAM, SDRAM stands for Synchronous dynamic random access memory. This RAM uses transistors and capacitors. The capacitors are set to a voltage if they are to be a one, or they are cleared to no voltage if there is to be a 0. Since capacitors leak slowly, SDRAM must read and write every bit very often, which is called refreshing the RAM, this either fills the capacitor back to full, or keeps it at zero.

RAM is an electronic, or volatile, state. When the computer is off, RAM is empty; when it is on, RAM is capable of receiving and holding a copy of the software instructions and data necessary for processing. The Ram is used for the following purposes:
Storage of a copy of the main systems program that controls the general operation of the computer. This copy is loaded into RAM when the computer is turn on; it stays there as long as the computer is on.
• Temporary storage of a copy of application program instructions to be retrieved by the central processing unit (CPU) for interpretation and execution.
• Temporary storage of data that has been input from the keyboard or other input device until instructions call for the data to be transferred into the CPU for processing.
• Temporary storage of data that has been produced as a result of processing until instructions call for the data to be used again in subsequent processing or to be transferred to an output device such as the screen, a printer, or a disk storage device.
• RAM chips are often called dynamic RAM (DRAM) chips, based on the style of the electric circuits.
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December 24, 2010 - Posted by | Computer

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