The terms "BIOS" and "CMOS" are often used interchangeably, even by computer experts, but the components are not identical: the CMOS contains information about how each device installed to the PC is configured, while the BIOS retrieves this data at startup to initialize the connected hardware. Additionally, any changes you make to your hardware settings via the BIOS setup utility are applied to the CMOS. If your ASUS P5B Deluxe freezes intermittently, restarts without warning or exhibits other signs of instability, you can reset the CMOS as a troubleshooting measure.
Turn off the computer, and then disconnect the power cord and any devices attached to the PC.
Loosen and remove the thumbscrews or crosshead screws securing the case cover to the computer.
Slide the cover towards the back of the computer, and then lift the cover off the case to reveal the motherboard.
Touch the chassis or put on an antistatic wrist strap to ground yourself and protect your hardware from static electricity.
Shine a flashlight on the motherboard and locate the "CLRTC" jumper, positioned between the RAM and the chipset.
Move the jumper shunt from pins 1 and 2 to pins 2 and 3. Return the shunt to its original position after 10 to 15 seconds.
Reassemble and then turn on the computer. Press "Del" when the ASUS logo appears to enter the BIOS setup utility and reconfigure your hardware settings, if necessary.