32GB (4x8GB) DDR3-1600MHz PC3-12800 ECC UDIMM 2Rx8 1.35V Unbuffered Server Memory by NEMIX RAM at Amazon.com
OWC 32GB (2 x 16GB) PC10600 DDR3 ECC-R 1333MHz DIMMs Memory Compatible with Mac Pro Early 2009 & Late 2010 'Nehalem' & 'Westmere' Systems and Early 2009 Xserve. (OWC85MP3S9M032K) at Amazon.com
Dell 32GB RAM PC3-10600 DDR3-1333MHz CL9 240-Pin Certified LRDIMM for Select Dell Systems A6994475
32GB (4 x 8GB) DDR3 PC3-10600 1333MHz ECC RDIMM Server Memory