Hi everyone, I recently wanted to upgrade the Ram speed my alienware PC that I bought from the Nov 2016 to make it to run faster. I had tried to look up multiple videos and article about how the whole process. However I got stuck on the step on the BIOS, which I couldn't enable overlock feature to change my RAM from 2133Mhz to 2400Mhz, since the overlock option on my BIOS is grey out and not able to select it. So I would like to ask if anyone know how to enable the overlock feature to select either XMP 1 and 2 in this situation? And also I would like to provide some basic information below to help if any of the information is able to determine whether my PC are able to upgrade the RAM speed or not. I appreciate for any help or suggestion. 

BIOS Version: 1.0.11

Product Name: Alienware Aurora R5

Motherboard: Alienware 01NYPT (100 Series / C230 Series)

CPU Type: Intel (R) Core (TM) i7-6700 CPU @3.40 GHz

CPU Speed: 3400 MHz

System Memory: 8192 MB (DDR4)

Memory Speed: 2133Mhz

Installed RAM: 8GB

System Type: 64-bit operating system, x64-based processor