Memory bandwidth is depending on chipset, processor, and supported FSB or Intel QPI (Nelalem Architecture) of your motheboard. Desktop memory is Unbuffered Non-ECC or ECC. Server memory is Registered ECC or Fully Buffered ECC. Email me if you have any questions. DDR2-400 Registered ECC DIMMs (800MHz Intel EM64T Xeon) DDR2-533/667 Unbuffered DIMM (Intel LGA775 Processor) DDR1 Unbuffered DIMMs (Intel 478-pin Processors) DDR1 Registered ECC DIMMs (Server) PC133 REG ECC DIMMs (Used) DDR2-667 PC2-5300 Fully Buffered DIMM - for Intel S5000PAL & S500PSL DDR2-800 PC2-6400 Fully Buffered DIMM - for Intel S5400SF & D5400XS Desktop Unbuffered Non-ECC DDR2-800 JDEC DIMMs PC-800 & PC-1066 Rambus Memory RAID Mini DIMM for Intel Active SAS / SATA RAID Mid-Plane in SR2500ALLXR DDR3-1333 Registered ECC DIMMs for Intel S5500 & S5520 Desktop Unbuffered Non-ECC DDR3-1333 JDEC DIMMs