Arithmetic and logical unit are responsible for all computationally intensive task which determines the speed and reliability of a processor. In other word we can say ALU is the brain of a processor. Nowadays every portable devices are battery operated so primary concern of those devices are low power consumption. But at the same time we want higher performance also so that there should not be any lag while using those devices. Graphically intensive application demands more resources and at the same time demands more power. Optimization between speed of operation and power consumption is the key challenge in design paradigm. The performance increase can be achieved by increasing clock frequency, but it leads to some other issues such as overheating, leakage etc.