Samsung’s new 850 EVO product line is powered by the company’s new MGX controller. A controller with a low power 2-core design, this drive will be amongst the fastest we have ever tested. Bear in mind that the 1 TB models of the EVO series will get the MEX controller based on a 3 core ARM design. It’s not just about performance though, it is about endurance as well. In a nutshell, endurance is the number of program-erase cycles an SSD has before you can’t write onto it anymore.