A proven approach to increase performance of general-purpose processors is to add hardware accelerators. In its basic configuration, the FlexCore processor has a limited set of datapath units. But thanks to a flexible datapath interconnect and a wide control word, the FlexCore datapath is explicitly designed to support integration of special units that, on demand, can accelerate certain data-intensive applications. We present the integration of a versatile accelerator for several Cyclic Redundancy Checking (CRC) keys. Furthermore, we investigate the accelerator’s impact on processor execution time and energy efficiency, using the Power Stone CRC benchmark. Our evaluation shows that the accelerated 65-nm 2.7-ns FlexCore datapath is, for example, 86% more energy and cycle efficient than a datapath lacking the CRC accelerator.