Chassis as part of the computer accessories, the main action since it is placed and fixed computer accessories, each have a retainer and protection effect, in addition, the important role of computer case with electromagnetic radiation shielding, because the case is not like CPU, video card, motherboard and other accessories can rapidly improve the machine performance, therefore has not been listed as a key consideration in the DIY object. But the case is not useless, some users after buying a less known and inferior brand case, because the motherboard and chassis form a loop, cause a short-circuit and make the system become very unstable.