SERVER RAM

ECC Registered Server RAM-

Server memory is generally ECC Registered (buffered). There are extra chips on the module that provide error correction and data checking functions. It is easy to spot ECC Registered Server RAM by looking at the chips on the module.

While desktop memory usually has eight chips per side, server memory has 9 large or 18 half-size chips per side, plus two or three smaller "register" chips. The 9th (and 18th) DRAM chips provide the error 

correction function, and the additional "register" chips hold the data for one clock cycle (ie act as "buffers") to increase the reliability of high-speed data access.

Unless your machine specifically supports ECC Registered memory your machine will not function correctly and may not even boot with this type of memory installed.

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ECC Unbuffered RAM

Many workstation computers and some servers use ECC unbuffered RAM. ECC unbuffered RAM looks similar to standard desktop memory, but instead of 8 chips per side it has 9 chips per side. The 9th chip handles the error correction function in machines that support ECC memory.

It can be confusing because server RAM is often referred to as simply "ECC RAM", but ECC unbuffered is not the same as ECC registered. If your machine uses DDR2, DDR, or SDRAM and requires ECC unbuffered memory, in most cases ECC registered is not compatible. Server motherboards that use DDR3 memory can often use either ECC unbuffered or ECC registered, however you cannot use both types in the same machine at the same time.

To be absolutely certain what memory type you are running, look at the memory currently installed in your machine and check your product manual.

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ECC Fully Buffered Server RAM 

FB-DIMMs (aka fully buffered) are a type of ECC RAM which use an Advanced Memory Buffer (AMB) between the memory controller and the memory module. The notch on FB DIMM memory is offset to prevent these modules from being installed in systems which use standard DDR2 RAM. Future development of this memory type is uncertain. We do not carry FB-DIMMs at GeeK NoiZe because there are no benchtop memory testers available which can test this type of module.