Step 1: Turn off your PC, unplug the power cable and open your system unit. Touch the chassis of the casing with a metallic object to discharge static electricity.
Step 2: Check the documentation for your motherboard to locate the position of the jumper that resets the BIOS. If you don't have a manual, look on your motherboard for one of the following tags: CLR BIOS, CLEAR BIOS, CLR CMOS, CLEAR CMOS, RESET BIOS or RESET CMOS. If the jumper is on 2-connector pins and it is held on a single pin, place it on both, wait one second then return it to its original position.
Step 3: Find the jumper on your motherboard reset it. It is usually close to the battery.If the jumper is on 3-connector pins, place it on the middle and the initially uncovered pins. Wait for some time and put the jumper in its original position (PIN1-PIN2).If the jumper is on a 2-connector pins and that is holding on a single pin, place it on both, wait one second and then return it to its original position.
Step 4: Power up and start your PC: the password will have disappeared.
Note: atmost care should be taken while performing these actions.do in supervision of an expert.....