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Command Prompt Secrets for Windows Problem-solving

Just like people, when computers lack energy, they forget things. Your PCs BIOS (Basic Input Output System) operates at a level below the Windows operating system, directly controlling the computers hardware. The BIOS is permanently stored in the PCs hardware, although it can be updated in certain circumstances. However, the configuration of every PC is slightly different. For example, you might have added a new CD writer or a second hard drive. The BIOS stores this type of information in CMOS (Complementary Metal Oxide Semiconductor) RAM (Random Access Memory). The values stored in the CMOS RAM require a battery to remain readable. Just like the RAM that your PC uses to run software, the CMOS RAM is wiped when the power is turned off. To avoid having to enter the BIOS information each time that you start your PC, the CMOS RAM is maintained by a small battery that preserves the contents. This battery also powers the system clock, which displays the date and time inside Windows. In the following article, you will learn how to replace this CMOS battery when it is failing.

Category: Troubleshooting
Issue: 2010 Issue 8 November/December
Operating Systems: XP, Vista, 7
Article Reference: C4