8GB -2X4GB- Memory Ram Compatible with HP/Compaq Workstation Z800 Ecc Reg for Server Only by CMS B37

2pcs 4GB PC3-10600 DDR3-1333MHZ 240-pin ECC REGISTERED SDRAM DIMM. Lifetime warranty BRAND Computer Memory Solutions Compatible with HP/Compaq Workstation Z800 Maximum Memory: 48GB ECC UDIMM 192GB RDIM Expansions: 12 Sockets System Part Numbers: FF825AV; FG639EC; FL848UA; FL849UA; FL850UA; FL851UA; FL875UT; FL876UT; FL877UT; FL878UT; FL879UT; FL881UT; FX465AV; KK533EA; KK543EA; KK544EA; KK561EA; KK562ET; KK563EA; KK564ET; KK577EA; KK584ET; KK599ET; KK600ET; KK604EA; KK629EA; KK644EA; KK658ET; KK659ET; VA789UA DDR3 1333MHz speed requires Intel Xeon X5550 or higher processors. 1066MHz requires Xeon E5520 or higher, Xeon E5506 or lower support 800MHz only. Memory speed will be reduced as the number of modules installed increases. 1333MHz is supported with one DIMM per channel only using Xeon X55xx series. THIS DDR3-1333 modules can automatically clock down to 1066MHz and 800MHz depending on module configuration or processor model installed. Due to chipset limitations, DDR3 Quad Rank memory will operate at 1066MHz in the first Triple Channel bank. Adding Quad Rank modules in the second Triple Channel bank will operate at 800MHz. This system supports either Registered ECC or Unbuffered ECC memory. Mixing Registered ECC and Unbuffered ECC modules is not supported within this system. 4GB DDR3-1333 Reg ECC modules come in two versions: 313/4G using x4 and 3138/4G using x8 DRAM. The two parts may be installed in the same system but not within the same memory bank. Use like modules for dual and triple channel operation.