Transcend 4GB DDR3 1866 ECC-DIMM CL13 2Rx8 - For Server - 4 GB DDR3 SDRAM - 1866 MHz - CL13 - 1.50 V - ECC - Unbuffered - 240-pin - DIMM - Lifetime Warranty

No matter how heavy and numerous the applications that you are using, 1866 MHz memory speed with Unbuffered signal will run them smoothly 4 GB of memory to refine your computers performance DDR3 SDRAM operates at an effective bus speed with minimal power consumption and as a result, you get optimal computer performance with an improved memory heat dissipation