IBM 8GB PC2-3200 DDR2 400Mhz ECC CL4 276Pin DIMM 15R7448 at Amazon.com
CMS 4GB (2X2GB) DDR2 3200 400MHZ ECC Registered DIMM Memory Ram Upgrade Compatible with Dell® Precision Workstation 470 for Server Only - B69 at Amazon.com
MicroMemory 2GB KIT DDR2 400MHZ ECC/REG at Amazon.com