Among the components of a PC, there are several essential elements that should
not choose at random: the processor, motherboard, graphics card and memory.
These four elements have a direct and significant influence on the functionality
and performance that you issue your computer. Now lets see memory timings and
their usefulness in practice.
Memory is a crucial part in the
performance and stability of a PC.There are other criteria such as speed,
latency, capacity, etc.. It is these elements that to deal with numerical
The storage of information is the same as other media used in computers, ie
binary form of 0 and 1. The bit cell is the unit of this type of memory, he took
the value of a 0 or a 1. It includes these bits table cells in multi-million for
memories of different sizes.
The table structure allows you to send a
bit cell with a coordinated intersection of a row and a column. It is therefore
easy to read or write data when you want it to memory, knowing only the address
of the bit cell concerned. The reading or writing data is done from anywhere of
memory with the same access time. That is why it is called Random Access Memory
or RAM. All submissions current work on this principle.
Dynamic memory or DRAM
DRAM or Dynamic RAM is so named because it is obliged to refresh to work
The bit cell consists of a couple physically transistor and
capacitor. The transistor connects the intersections of the table (in a sense,
it's a switch) and is then connected to a capacitor that stores the state 1 or 0
corresponding to a load or no load.
The capacitor was chosen for its
simplicity of manufacture, its very small footprint and hence its cost. It is
easy to use on a much smaller area to produce large memory while modules with
small and inexpensive.
- The load and discharge are not instantaneous which determines the latency of
- A capacitor loses its charge over time, they say it leaks. It may not keep
the information in a short time, that is why the memory is refreshed
A memory card is composed of several chips. Each chip is divided into "banks".
Each bank is an array . Each table cell contains 1 byte of data (8 bits). For
example: 256 MB of memory consists of 8 chips of 32MB each chip contains 4 banks
of 8 MB (8192 = 024 lines x 1 column x 1 byte).
For DDR-2 are made from
chips of 128 MB (by increasing the fine print), which are then used to construct
512 MB DIMMs (equipped with 4 chips), 2GB (equipped with 16 chips) ...
The memory currently in the most widespread is the DDR SDRAM (Double Data Rate)
which, like the RAMBUS uses two fronts so as to treat twice as much data as the
frequency equal to SDRAM (DDR PC1600 to PC2100 and 100 MHz to 133 MHz). The
format is still used but the DIMM slots from