The Corsair Obsidian 650D has a the ATX form factor. ATX is the most ubiquitous of case standards, providing the largest array of compatible hardware on the market. Using the ATX standard, the case can house motherboards and power supplies with form factors ATX, E-ATX and Micro-ATX. The dimensions of the case itself (LxWxH) are 546mm x 229mm x 521mm.

The Corsair Obsidian 650D has seven expansion slots, so there is plenty of room for extra components, which may be a deciding factor when planning on the longevity and build type of a PC system. The case has four 5.25" drive bays, which is enough to house an optical drive and a couple of hard drives, while still having space for plenty more HDDs with the six 3.5" drive bays that are also available. You can even install an SSD or laptop-sized HDD using one of the six 2.5" drive bays. Installation of hard drives into these drive bays is made all the more easier by screwless rails that allow tool-less mounting.

Made primarily of Aluminium, the Corsair Obsidian 650D is built to be strong, lightweight, and well-ventilated. This often comes at a price premium, but some see the benefits to be completely worth it. Whatever your case's material, it is important to keep a consistent airflow so that heat doesn't build up inside. It is therefore advised that you make use of the available built-in case fans and fan installation sections.