Resetting the CMOS the Hard Way
In many cases, BIOS issues and other lower-level device failures can be attributed to poor CMOS settings that might had been modified by a client; to fix these issues, a simple reset of the CMOS is oftentimes enough.
If you are having difficulty locating the CMOS reset jumper, however, don't worry too much. All you have to do is remove the battery so that the charge is lost. First, unplug the PC in question.
Then, locate the battery (typically a silver CR2075 battery) and remove it from the motherboard for at least one minute.
Insert the battery back into place, turn on the PC, and the default BIOS setting should be set.