A computer’s RAM refers to the computer’s Random Access Memory. It is a form of data storage that enables the user to access data in any order with a worst case performance of a constant time. RAM can be classified into volatile types of memory, some of which include the dynamic RAM. Volatile memory is memory that loses data when the power of a machine or device is switched off. Other types of RAM are not volatile. These do not lose the data when the power of a machine or device is switched off.
PC Memory RAM (DDR SDRAM)
PC refers to a double data rate synchronous dynamic random access memory interface. It has superseded PC memory RAM. Sometimes PC memory is also called DDR SDRAM. DDR SDRAM refers to Double data rate synchronous dynamic random-access memory. It is a class of memory integrated circuits used in computers. This class of memory integrated circuits interface makes the transfer of data to reach very high rates. This is due to their strict control of timing of electrical data and clock signals. Implementations use schemes such as phase-locked loops and self-calibration to reach the required timing accuracy. The interface uses double pumping to lower the clock frequency.
PC 2 Memory RAM (DDR 2 SDRAM)
It is also a double data rate synchronous dynamic random access memory interface. It is the random access memory interface that supersedes the afore-mentioned DDR SDRAM. Any advancement of these dynamic random access memory interfaces is not forward or backward compatible. This implies that the upcoming dynamic random access memory interfaces will not operate in any system that is suitable for the memory interface that preceded it. PC2 Memory RAM allows higher bus speed and requires lower power. It is able to do so because it runs the internal clock at half the speed of the data bus. The combination of these two factors results in the memory interface to require a total of four data transfers per internal clock cycle. For example if the data is being transferred at 64 bits at a time, then PC2 Memory RAM will give a transfer rate of 64x2x2/8 number of bits/bytes. A more general example is when a system’s memory clock transfer is 100 MHz. In this case you expect PC2 Memory Ram to give it a maximum transfer rate of 3051.75 MB/s. Compared to DDR SDRAM memory operating at the same external data bus clock rate as PC2 Memory Ram; DDR2 SDRAM is able to provide the same band width, but with a higher latency.
The PC 2 Memory RAM (DDR2 SDRAM) make up
DDR2 SDRAM stores its data in memory cells. The memory cells are activated with the use of a clock signal to synchronize their operation with a data bus from the external. The bus frequency of PC2 Memory RAM is boosted by electrical interface improvements. Other features which enhance the bus frequency are on-die termination, pre-fetch buffers and off-chip drivers. The chips are packaged in BGA. This is a more expensive and more difficult manner to assemble. This manner of packaging is vital for maintaining signal integrity at higher speeds.