parts-quick 8GB (2 X 4GB) DDR2 Desktop Memory PC2-5300 240 pin 667MHz Non-ECC DIMM RAM at Amazon.com
CMS 8GB (2X4GB) DDR2 5300 667MHZ ECC Fully BUFFERED DIMM Memory Ram Compatible with HP/Compaq Workstation Xw8600 Series Ddr2-Pc5300 Fb for Server Only - B54 at Amazon.com
Kingston ValueRAM 8GB DDR2 667MHz Reg with Parity DIMM Desktop Server Memory at Amazon.com
Komputerbay 2GB DDR2 667MHz PC2-5300 PC2-5400 DDR2 667 (200 PIN) SODIMM Laptop Memory - Komputer Bay