When users wish to over-clock the memory module, they must manually adjust relevant parameters, such as clock speed, working voltage, CL, tRCD, tRP and tRAS from the BIOS. Therefore, unless the user has rich overclocking experience, he will need to try different combinations in order to find out the best settings for the module to display its optimal performance. Therefore, it is time- and labor consuming, especially to beginners. As a solution, NVIDIA extended the SPD by adding more parameter combinations to the unused space, about 29 bytes, in conventional SPD. As long as the supported motherboards are used, the BIOS can automatically detect the optimal module settings to easily release the performance of modules. This feature is called the EPP, Enhanced Performance Profiles.