Unbuffered memory is commonly used for laptops
and PCs where buffering data is not so critical. These modules are basically faster
than buffered memory since data pass from RAM to chipset or motherboard directly and without much
Buffered memory and registered memory are
essentially the same in that they contain logical components called “buffers”
or “registers” that help the chipset manage the proper address loading of data.
This is particularly helpful when large volume of data is being processed that
is why modules of this type are usually required on most servers where reliability
is very critical. These modules have higher latency, which makes the initial response to
be slower than unbuffered modules.
The term “ Buffered” often refers to
asynchronous modules, that is, EDO and FPM memory, while “Registered” is used for
synchronous memory or SDRAM.
Physically, you can easily identify a module is
registered because it has additional chips usually located at the bottom of the
module which increases its height. Some
rackmount solutions require the standard height modules so these extra chips
are placed between the row of DRAM chips. These modules are known as low profile registered
Registered and Unbuffered modules cannot be used
simultaneously in one system.