<-------------------RAM------------------>

Subject: <-------------------RAM------------------> Mon Aug 13, 2012 1:29 pm

<-------------------RAM------------------>
Random access memory (RAM) is the best known form of computer memory.
RAM is considered "random access" because you can access any memory cell
directly if you know the row and column that intersect at that cell.
The opposite of RAM is serial access memory (SAM). SAM stores data as a
series of memory cells that can only be accessed sequentially (like a
cassette tape). If the data is not in the current location, each memory
cell is checked until the needed data is found. SAM works very well for
memory buffers, where the data is normally stored in the order in which
it will be used (a good example is the texture buffer memory on a video
card). RAM data, on the other hand, can be accessed in any order.

Similar to a microprocessor, a memory chip is an integrated circuit (IC)
made of millions of transistors and capacitors. In the most common form
of computer memory, dyn
amic random
access memory (DRAM), a transistor and a capacitor are paired to create a
memory cell, which represents a single bit of data. The capacitor holds
the bit of information -- a 0 or a 1 (see How Bits and Bytes Work for
information on bits). The transistor acts as a switch that lets the
control circuitry on the memory chip read the capacitor or change its
state.
A capacitor is like a small bucket that is able to store
electrons. To store a 1 in the memory cell, the bucket is filled with
electrons. To store a 0, it is emptied. The problem with the capacitor's
bucket is that it has a leak. In a matter of a few milliseconds a full
bucket becomes empty. Therefore, for dynamic memory to work, either the
CPU or the memory controller has to come along and recharge all of the
capacitors holding a 1 before they discharge. To do this, the memory
controller reads the memory and then writes it right back. This refresh
operation happens automatically thousands of times per second.
he
capacitor in a dynamic RAM memory cell is like a leaky bucket. It needs
to be refreshed periodically or it will discharge to 0. This refresh
operation is where dynamic RAM gets its name. Dynamic RAM has to be
dynamically refreshed all of the time or it forgets what it is holding.
The downside of all of this refreshing is that it takes time and slows
down the memory.
In this article, you'll learn all about what RAM
is, what kind you should buy and how to install it. See the next page to
learn more about dynamic RAM and memory cells.

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Posts : 46 Points : 54 Join date : 2013-06-05

Hello,
Nice info thanks for sharing...