16GB KIT (8 x 2GB) For Dell Precision Workstation Series 490 690 (1KW) 690 (750W) 690n (1KW). DIMM DDR2 ECC Fully Buffered PC2-4200 533MHz RAM Memory. Genuine A-Tech Brand. 16GB KIT (8 x 2GB) DIMM DDR2 ECC Fully Buffered PC2-4200 533MHz RAM Memory Genuine A-Tech Memory Lifetime Warranty Toll Free Technical Support 1-866-557-4527 Designed For Dell Precision Workstation Series. (See Compatibility List Below)