8GB KIT (4 x 2GB) For Fujitsu-Siemens Primergy Series TX100 S2 (ECC Unbuffered) TX200 S6 (ECC Unbuffered). DIMM DDR3 ECC Unbuffered PC3-8500 1066MHz RAM Memory. Genuine A-Tech Brand. 8GB KIT (4 x 2GB) DIMM DDR3 ECC Unbuffered PC3-8500 1066MHz RAM Memory Genuine A-Tech Memory Lifetime Warranty Toll Free Technical Support 1-866-557-4527 Designed For Fujitsu-Siemens Primergy Series. (See Compatibility List Below)