4GB 800MHz DDR2; Patriot Memory's Signature Line DDR2 Non-ECC Unbuffered memory delivers quality, reliability and performance expected for today's computer needs. This 4GB module is designed to run at PC2-6400 (800MHz) at CAS 6 latency timings. Built using specific build-of-materials (BOMs) we ensure that every module meets and exceeds industry standards: offering you a hassle-free upgrade.