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CMS 8GB (2X4GB) DDR2 5300 667MHZ ECC Fully BUFFERED DIMM Memory Ram Upgrade Compatible with HP/Compaq® Workstation Xw8600 Series Ddr2-Pc5300 Fb for Server Only - B54 at Amazon.com
8GB Kit (4x2GB) Fully Buffered DDR2 Server Ram/Memory. PC2-5300 667MHz DDR2 DIMM ECC (Fully Buffered) 240 Pin 1.8V at Amazon.com