Kingston H. Corporation ECC CL4 DIMM (Kit of 2) Desktop Memory 4 Dual Channel Kit 533 MHz (PC2 4200) 240-Pin DDR2 SDRAM KVR533D2E4K2/4G Kit includes 2 2GB modules of 533MHz DDR2 Desktop Memory Specifically designed and tested for compatibility in various makes and models of desktop computers From the industry leader in PC memory Backed by a lifetime warranty and free technical support