Kingston ValueRAM 4GB Kit (2x2GB Modules) 800MHz PC2-6400 DDR2 CL6 DIMM Desktop Memory (KVR800D2N6K2/4G) 4GB kit including two 2GB modules of 800MHz DDR2 Desktop Memory Specifically designed and tested for compatibility in various makes and models of desktop computers CL6 240-pin unbuffered DIMM From the industry leader in PC memory Backed by a lifetime warranty and free technical support