Included in the package is a Genuine A-Tech Brand 4GB Single DDR2 PC2-5300 / PC2-667 2rx4 1.8v ECC FULLY BUFFERED SERVER Memory Module (240-pin DIMM 667MHz) upgrade. The A-Tech 397415-B21-ATC is equivalent to the HP Genuine 397415-B21 and serves as a compatible replacement for or expansion of existing OEM installed modules. A-Tech is one of the most trusted names in Premium Memory. Backed by a Lifetime Warranty and 5 star customer support, A-Tech has you covered! Memory upgrades have never been easier. Designed specifically to help your computer run faster and smoother, an A-Tech memory upgrade is one of the fastest, most affordable, and easiest ways to improve your system's performance. A-Tech memory empowers your computer to achieve faster application loading times, faster system responsiveness, and increased ability to multitask and handle data-intensive programs. A-Tech modules are rigorously tested to ensure that your memory meets our stringent compatibility and performance standards. Every A-Tech ram module is tested for complete functionality before it leaves our doors. Give your computer the best, trust A-Tech!