There are two main types of random access memory (RAM); these are buffered memory — or registered memory — and unbuffered memory, otherwise known as unregistered memory. Unbuffered memory is faster, more common, and considerably cheaper to purchase than buffered memory. As such, these unregistered memory forms are the module type found in almost all home desktop and laptop computers. Buffered memory is more expensive than the unbuffered type, and it is also slower due to the way in which it handles data storage and recovery. Buffered memory is, however, far more stable than unbuffered forms so it is utilized mostly in mainframe and server network computers.
Unbuffered memory is by far the most common form of computer memory module found in day-to-day use. These memory modules are cheap to produce in comparison to buffered memory modules, partially due to their common use in domestic and commercial computers and also due to the fact that there is less hardware utilized. In an unbuffered memory module, there is no form of onboard hardware to act as a register for instructions between the RAM chip and the computer’s memory controller. This results in a faster operating speed but an increased risk of a critical memory-loss error occurring because of the random nature of information placement and recovery, especially during periods of intensive activity.
More commonly referred to as registered memory is buffered memory. Unbuffered memory, oddly, retains its name and hasn’t been changed to unregistered memory. Buffered memory differs from the unbuffered type in that it features a hardware register that stores information in a cache for one clock cycle of the memory chip. While this operation can result in a slower run time for the memory chip, it does provide additional stability and a reduced risk of memory errors or corruption.
In general domestic use, the speed difference between the two kinds of memory module seems negligible. It is during periods of intensive information transfer that the latency experienced through the use of the register becomes apparent. Buffered memory is commonly used in server computers and mainframe systems to provide the stability and protection against corruption that may occur in unbuffered modules when they are subject to continual intensive use. While the buffered modules are more expensive and generally slower in operation, the stability of the memory and security of data more than compensates in a commercial environment.