A computer's BIOS can be accessed to alter computer's processor speed. By adjusting a processor's speed can also improve the performance, ease the heat or correct the system error. By increasing the processor's speed which will improve the performance is known as overclocking or to change the processor to its default speed. Apart from this you can decrease processor speed to reduce the operating temperature.
1. First thing to do is switch on the computer and press any one F1,F2, Del, Esc or F10 button to access system's BIOS when the motherboard's boot splash screen appears. The boot splash screen may contain the text showing which button to be pressed as it the button mainly depends on the manufacturer. You have to press the button before the DOS starts running system diagnostics or Windows loading screen appears.
2. Go through the BIOS setup menu by following the arrow and press enter key to select. Then find the CPU multiplier, frequency or a ratio option as each version of the BIOS have a similar process and few may have different names for processor adjustment features. This option may take you to the advanced or overclock heading. Next select the option which says CPU multiplier/frequency/ratio with the arrow keys and then press Enter.
3. Select lower multiplier number on the menu to slow down the processor and select higher number on the menu to increase the speed of the processor. To speed up the processor you have to increase the multiplier and check computer's operating temperature to continue with further adjustments. Next choose Exit menu using arrow keys, then Save and Exit option.
4. Press BIOS key after restarting the computer again and look at the processor's operating temperature which appears on default screen and the computer will run for 10-15 minutes. If the processor reaches more than 130 degrees change it to the original setting.