Your Mac Pro has 4 slots and the maximum possible upgrade is 128GB (4x32GB). Total Capacity: 128GB. Ram speed is limited to 1066Mhz. INSIDE YOUR MAC PRO 2013.
16GB (2 x 8GB) DDR4 2666MHz PC4-21300 Samsung Laptop RAM 260pin Memory Ram
Samsung 16GB 8GB 4GB 2Rx8 PC3-10600S DDR3-1333Mhz SODIMM Laptop Memory RAM
Crucial 16GB 2X8GB DDR3 2RX8 1600MHz PC3L-12800S 204pin Laptop Memory RAM
CRUCIAL DDR3L 16GB (8GB x2) 1333mhz PC3L-10600 Laptop SODIMM Memory RAM 204Pin
CENTON RD725G01 4GB PC3-10600 DDR3-1333MHz ECC Reg 244-Pin MiniDimm Memory Ram
32GB -2x16GB Memory Ram Upgrade For Apple Mac Pro 6.1 (2013) all CPUs 1866Mhz
