HP DDR4 2666 MHz DIMM Non-ECC Overview Boost the capabilities of your Z2 Mini, Tower, or Small Form Factor G4 Workstation with the 4GB DDR4 2666 MHz Non-ECC Memory Module from HP. Featuring a capacity of 4GB and a clock speed of 2666 MHz (PC4-21300), this non-ECC DDR4 memory module is designed to improve system performance and application responsiveness. Start-up times will be improved with fewer delays during routine operations, and more programs will be able to run simultaneously.