RAM memory types: RDRAM, SDRAM, DDR and beyond
RAM (Random Access Memory) is the component which stores data transiently and supplies data to and fro from the processor and the hard drive. RAM is an intermediate between these two and is slower than the processor but runs faster than your hard drive. Some of the basic information you need to essentially know about RAM is they are of two types 1) Synchronous DRAM (SDRAM) 2)Double Data Rate SDRAM (DDR). There was yet another type of RAM called Rambus DRAM or (RDRAM) but is obsolete now.
SDRAM is quickly becoming obsolete technology and has been replaced by faster and more efficient DDR type of RAM. DDR is a 184 pin DIMM(Dual Inline Memory Module) dynamic RAM unlike SDRAM which is static 168 pins DIMM. Both differ in physical form and require different voltage to run.
Coming to different types of DDR RAM there are umpteen number of variations and combination, and when it comes to types DDR RAM comes in three flavors compatible with mainstream motherboards DDR1, DDR2 and DDR3. DDR RAM is classified based on its speed and latencies, DDR1 RAM could run upto a maximum speed of 400Mhz and had varying latencies. DDR2 starts off with 400Mhz and can go upto 800Mhz, DDR3 being the latest generation RAM can go upto 2000Mhz (1600Mhz is standard) and have low latency compared to previous generation and consumes less power.
Latency plays the most important role since it determines the time it takes to access data stored in RAM. So lower latency RAM offers better performance and this in-turn shows up in the performance of the entire system. DDR3 offers the best of both worlds as in lower latency and less power consumption and the higher data rates are unmatched by older generation RAMs. DDR1 is almost obsolete and DDR2 usage is on the decline, DDR3 being the latest is seeing a price drop at regular intervals so if you are planning to buy RAM this is the right time with online shopping offering more and more discounts and offers, DDR3 is the way to go for the future.







