CompTIA A+® Certification All-In-One For Dummies®, 2nd Edition

4.5. Viewing Advanced CMOS Settings

Many newer systems maintain the basic CMOS parameters mentioned in the previous section but are also supplemented by different advanced setup settings. This section examines the purposes and characteristics of some of these advanced settings.

4.5.1. Globally Unique Identifier (GUID)

The Globally Unique Identifier (GUID) is a 128-bit number, randomly generated for the system when it was built, and stored in CMOS. The GUID uniquely identifies the system from any other. It enables the identification of individual computers and ensures that this identification method is absolutely unique.

Many features in today's computers make use of the GUID. For example, one of the Windows installation tools (Remote Installation Services; RIS) allows the administrator to go into a client computer's CMOS, make a note of the GUID, create a computer account within Windows Active Directory (AD) database for the workstation, and associate the GUID with the account. If the client computer is booting off the network when it starts, it contacts the RIS server and starts installing a Windows client OS. The client computer uses the computer name of the computer account found in Windows AD that its GUID is associated with.

Some systems have adopted the term UUID (Universally Unique Identifier) instead of GUID. You might see a UUID in CMOS instead of a GUID, as shown in ...