8GB Kit 2 X 4GB DDR2 Server Memory Upgrade for IBM System x3550 1913, 7978-xxx SDRAM ECC Fully Buffered FB DIMM PC2-5300 240 pin 667MHz RAM (PARTS-QUICK Brand) at Amazon.com
4GB Kit (2x2GB) Fully Buffered DDR2 Server Ram/Memory. PC2-5300 667MHz DDR2 DIMM ECC (Fully Buffered) 240 Pin 1.8V at Amazon.com
Samsung M393T2950CZP-CCCQ0 1GB DDR2 Server RAM Memory – Buffalo Computer Parts
Micron 6GB Kit 6x1GB 1Rx4 PC2-3200R-333-12-C0 DDR2 Server Ram MT18HTF1