If your computer behaves erratically or runs unusually slowly, you may have a hardware problem, or a system setup problem. Occasionally a power line surge or a software bug can change the CMOS Setup in your computer. (The CMOS Setup refers to the low-level setup that your computer read in from battery-backed CMOS RAM when you boot it.) You can reach these setup screens by pressing a particular key when you boot your computer. (Usually your computer will briefly display a message at boot time telling you which key to press.)
The CMOS Setup contains many parameters which you must specify correctly for your computer to operate normally. Therefore if you are not a computer expert, you should find one before you change anything in your CMOS Setup.
Some CMOS Setup items can cause your computer to operate strangely if they have incorrect values. For example, if your computer has a 486 or Pentium chip, your CMOS Setup may have an option to disable your internal and/or external cache. Doing so can make your computer run dramatically slower.
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