504351-B21 Certified Memory for HP Proliant 8GB (2x4GB) DDR2 800MHz PC2-6400 240-Pin Low Profile Dual Rank ECC Reg. Server RAMSize/Capacity: 8GB (2x4GB)Speed: PC2-6400 (DDR2-800)Pins: 240Form: ECC Registered Warranty: Lifetime Replacement | 30 Day Money Back GuaranteeAll of our products are certified for your system. If at anytime you have a question on compatibility, or if this part is right for your specific computer, contact us ASAP through 's messaging system. We will get you the correct answer!Made from the highest quality components, ARCH MEMORY memory modules are designed to increase productivity and help your computer work faster. Arch Memory products are engineered to meet industry standard specifications and rigorously tested to ensure quality. Backed by a lifetime warranty and legendary reliability, Arch Memory RAM is your best choice for upgrading your computer's memory.