Cage or Rack-Designed Computer Frames/Cabinets

having a single module dedicated to one specific functional area. The chassis or assemblies can be mounted in one of several ways inside the computer’s frame or cabinet. These include brackets that permit the chassis or assembly to slide in and out of the frame or cabinet; doors that swing out from one side of the frame or cabinet; or a fixed chassis or assembly similar to a cage or rack inside the frame or cabinet. In some cases, a combination of two or more of these methods is used by a single computer. Chassis can slide out on mounting hardware, swing open like a door, or be fixed. Figure 2-11 is an illustration of a chassis or assembly-designed computer. The pcb’s inside a chassis or assembly are arranged in the same way as inside a module-in close proximity and configured in rows. Again refer to the computer’s technical manual for a chassis map that outlines the location of all parts of the computer. Each chassis or assembly contains subassemblies, pcb’s, and a power supply unit. Some computers use small brackets to secure the subassemblies or pcb’s inside each chassis or assembly. Each chassis or assembly is secured with retaining hardware. Check the computer technical manual to see if you can leave the power on while the assembly or chassis is extended or is being extended; it varies with the computer. This will affect the ability to extend subassemblies or pcb’s on an extender card with the power on. Support functions, such as power supplies and blower units, for chassis- or assembly-designed com- puters are usually located on a fixed chassis or assembly in the computer’s frame or cabinet. Chassis- or assembly-designed computers can also be water cooled. The functional areas that are basic to most chassis- or assembly-designed computers include the following: Cage- Central processing unit Input/output controller Input/output adapter Memory Power supply or Rack-Designed Computer Frames/Cabinets Computers that use cages or racks contain the following: Q A cage or rack Figure 2-11.—Example of a chassis- or assembly-designed computer. 2-10