The HP Z800 Workstation has a the XL-ATX form factor. XL-ATX is an unofficial larger version of the ATX standard which provides a larger alternative for even more space and ventilation. Using the XL-ATX standard, the case can house motherboards and power supplies with form factors Array. The dimensions of the case itself (LxWxH) are 526mm x 203mm x 444mm.

The HP Z800 Workstation has eight 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 three 5.25" drive bays, which is enough to house an optical drive and a couple of hard drives, while still having a couple of extra free hard drives with the four 3.5" drive bays that are also available. To mount an SSD you would require an adapter, however, as there are no 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 HP Z800 Workstation 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.