Is buffered memory better?

[dragonfly522]

What is the basic difference between unbuffered and buffered memory? Which is better?

 

[saint19]

Unbuffered memory is volatile memory which is the module of choice for personal computers and workstations while it is not suitable for high performance servers. Unbuffered memory is accessed directly by the memory controller where as Buffered Memory "caches" or stores and forwards the contents prior to the controller's access therefore buffered memory is more suited for server needs.
In the past, registered memory was called buffered memory and unregistered memory was called unbuffered memory. Registered memory got renamed in common use, but unbuffered memory did not.

Source

Registered (also called buffered) memory modules have a register between the DRAM modules and the system's memory controller. They place less electrical load on the memory controller and allow single systems to remain stable with more memory modules than they would have otherwise. Registered memory is more expensive because of the lower volume and the additional components, so it is usually found only in applications where the need for scalability and stability outweighs the need for a low price (servers, for example). Although most server-grade memory modules are both ECC and registered, there are both registered non-ECC modules and non-registered ECC modules.
Nominally, there is a performance penalty for using registered memory. Each read or write is buffered for one cycle between the memory bus and the DRAM, so the registered RAM can be thought of as running one clock cycle behind the equivalent unregistered DRAM. With SDRAM, this only applies to the first cycle of a burst.
However, this performance penalty is not universal. There are other factors involved in memory access speed. For example, the Intel "Westmere" 5600 series of processors access memory using Interleaving, wherein memory access is distributed across 3 channels. If 2 memory DIMMs are used per channel, this "...results in a reduction of maximum memory bandwidth for 2DPC (DIMMS per channel) configurations with UDIMM by some 5% in comparison to RDIMM." [1] (p. 14). This is because "...when you go to 2 DIMMs per memory channel, due to the high electrical loading on the address and control lines, the memory controller use something called a “2T” or “2N” timing for UDIMMs. Consequently every command that normally takes a single clock cycle is stretched to two clock cycles to allow for settling time. Therefore, for two or more DIMMs per channel, RDIMMs will have lower latency and better bandwidth than UDIMMs.

Source

I love Google

In easy words:

1- Buffered: More expensive and slower but with high reliability mostly used for servers and applications here is more important the reliability is more important that price and performance.

2- Unbuffered: For commune use in games and normal applications here is more important the price and speed that reliability.

 

[jaquith]

Registered memory is "better" and expensive. 99%+ consumer MOBO will not support Registered {Buffered} memory so it's a mute point.

In contrast, all of my Workstations & Servers with Xeon {not all Xeon support ECC/Registered} CPU(s) all use both ECC Registered memory. The chip-set for "consumer" CPUs memory controllers will not support either memory type.

 

[jaquith]

In easy words:

1- Buffered: More expensive and slower but with high reliability mostly used for servers and applications here is more important the reliability is more important that price and performance.

2- Unbuffered: For commune use in games and normal applications here is more important the price and speed that reliability.

Gaming in Churches lately?!

 

[dragonfly522]

Best answer selected by dragonfly522.