Amazon.com: OWC 32.0GB (4 X 8GB) ram Memory Upgrade kit DDR3 1333 mhz ECC PC 10600 SDRAM ECC, Compatible with 2009-2012 Mac Pro 'Nehalem' & 'Westmere' Models and PC desktops and laptops
Kingston PC3-10600 4 GB DIMM 1333 MHz DDR3 SDRAM Memory (KVR1333D3N9HK2/8G) for sale online | eBay