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The summarized overview of different DRAM chips is shown in the table below:


Where Used

Description and Facts


Dynamic Random

Access Memory

Main System

Memory and

Video Memory

DRAM is the most common type of computer memory.

DRAMs are used mostly in main memory systems.

DRAM is volatile and slow, but inexpensive. DRAM is

used for memory read and writes and the data must be refreshed after each transfer.


Fast Page Mode


Main System

Memory and

Video Memory

FPM is also commonly used as the main system memory.

As microprocessor speeds advanced, more memory

throughput was required, resulting in the development of

the Fast Page Mode DRAM.

FPM DRAM is similar to

regular DRAM but faster.


Extended Data

Output RAM

Main System

Memory and

Video Memory

EDO is an improvement on the FPM design.

Depending on the type of system and the software applications, EDO can provide approximately a 3% performance gain over

FPM DRAM if a secondary (L2) cache is in the system, and approximately a 10% to 12% performance gain if the L2 cache is not present.


Synchronous DRAM

Main System

Memory and

Video Memory

Synchronous DRAM is a new memory with improved

performance, simpler design, and faster transfer rates than

standard DRAM


Static RAM

Cache Memory

SRAM is an extremely fast device that does not require

periodic refreshing.

SRAM is used primarily in cache


SRAM is faster, bigger, and generates more heat than DRAM. It is also more expensive than DRAM


Enhanced DRAM

Cache Memory

EDRAM is positioned as a high-performance specialty memory that combines DRAM and SRAM caches on one chip


Video RAM

Video Memory

VRAM, specialized RAM for video, offers higher performance than DRAM.

VRAM is dual ported, which

allows simultaneous reads and writes of data.

It requires a larger package than DRAM, and is more expensive than DRAM, too.


Windows RAM

Video Memory

WRAM technology evolved from its predecessor, VRAM.

Named after its ability to offer full-motion video, WRAM comes in a smaller package than VRAM.

It has added intelligence that makes it perform up to 50% faster

than VRAM



Video Memory


Future generation of DRAM with performance increases of up to 20 fold over standard DRAM.

With costs just over 10% of standard DRAM, it is gaining acceptance in the industry