8GB Kit 2 X 4GB DDR2 Server Memory Upgrade for HP Workstation XW8600 SDRAM ECC Fully Buffered FB DIMM PC2-5300 240 pin 667MHz RAM (PARTS-QUICK Brand) at Amazon.com
Apple 64GB (8 x 8GB) DDR2-667 MHz PC2-5300F Fully Buffered– Cloud Ninjas
Amazon.com: OWC 2GB (2 x 1GB) PC5300 DDR2 667MHz SO-DIMMs Memory Compatible with MacBook/MacBook Pro, iMac, and Mac Mini Models (OWC5300DDR2S2GP) : Everything Else