The LG Optimus 4X HD is the first smartphone to use an NVIDIA Tegra 3 CPU. This processor has 4 physical cores clocked at 1.5 GHz. In addition, there is a fifth core clocked at 500 MHz that runs to perform small tasks such as music playback. The LG Optimus 4X HD has a 4.7″ screen which displays a 720p resolution a Li-Ion battery with 2,150 mAh. It initially ran on ICS and it was later upgradable to Android 4.1.2 Jelly Bean.
Since Jelly Bean no official updates are available for Optimus 4X HD. However Android 4.4.4 is available unofficially via CM 11 custom ROM developed by the CyanogenMod team. It will remove all the bloat and give a more Nexus like user experience. Follow the instructions given below to install CM 11 ROM on LG Optimus 4X HD.