4GB KIT (2 x 2GB) For HP-Compaq Business Desktop Series dc5800 (All Form Factors) dc5850 (All Form Factors) dc7800 (Small Form Factor/Convertible Minitower) dc7900 (Small Form Factor/Convertible Minitower) dx2310 dx2355 dx2358 dx2390 dx2400 dx2420 dx2480 dx2710 dx2718 dx2810 dx7400 (Microtower/Small Form Factor) dx7480 (Microtower) dx7500 (Microtower) dx7500 (Small Form Factor). DIMM DDR2 NON-ECC PC2-6400 800MHz RAM Memory. Genuine A-Tech Brand. 4GB KIT (2 x 2GB) DIMM DDR2 NON-ECC PC2-6400 800MHz RAM Memory Genuine A-Tech Memory Lifetime Warranty Toll Free Technical Support 1-866-557-4527 Designed For HP-Compaq Business Desktop Series. (See Compatibility List Below)