4GB KIT 2x 2GB HP Compaq Business Notebook 540 541 6710s C510 nc4400 nc6320 nc6340 nc8430 nw8440 nw9440 nx6315 nx6310 nx6330 nx7400 SO-DIMM DDR2 NON-ECC PC2-5300 667MHz RAM Memory Genuine A-Tech Brand 4GB KIT (2 x 2GB) SO-DIMM DDR2 NON-ECC PC2-5300 667MHz RAM Memory Genuine A-Tech Memory Lifetime Warranty Toll Free Technical Support 1-866-557-4527 Designed For HP Compaq Business Notebook. (See Compatibility List Below)