There are many different types of RAM which have appeared over the years and it is often difficult knowing the difference between them both performance wise and visually identifying them. This article tells a little about each RAM type, what it looks like and how it performs.

FPM RAM
FPM RAM, which stands for “Fast Page Mode RAM” is a type of Dynamic RAM (DRAM). The term “Fast Page Mode” comes from the capability of memory being able to access data that is on the same page and can be done with less latency. Most 486 and Pentium based systems from 1995 and earlier use FPM Memory.

FPM RAM

EDO RAM
EDO RAM, which stands for “Extended Data Out RAM” came out in 1995 as a new type of memory available for Pentium based systems. EDO is a modified form of FPM RAM which is commonly referred to as “Hyper Page Mode”. Extended Data Out refers to fact that the data output drivers on the memory module are not switched off when the memory controller removes the column address to begin the next cycle, unlike FPM RAM. Most early Penitum based systems use EDO.

EDO RAM

SDRAM
SDRAM , which is short for Synchronous DRAM is a type of DRAM that runs in synchronization with the memory bus. Beginning in 1996 most Intel based chipsets began to support SDRAM which made it a popular choice for new systems in 2001.
SDRAM is capable of running at 133MHz which is about three times faster than FPM RAM and twice as fast as EDO RAM. Most Pentium or Celeron systems purchased in 1999 have SDRAM.

SD RAM

DDR RAM
DDR RAM, which stands for “Double Data Rate” which is a type of SDRAM and appeared first on the market around 2001 but didn’t catch on until about 2001 when the mainstream motherboards started supporting it. The difference between SDRAM and DDR RAM is that instead of doubling the clock rate it transfers data twice per clock cycle which effectively doubles the data rate. DDRRAM has become mainstream in the graphics card market and has become the memory standard.

DDR RAM