BIOS - Press F1 to start the system

October 2016

This is for users who often encounter the error message saying 'Press F1 to start the system' when their desktop computer is booted. The only reason for this is that the CMOS battery life has expired and the CMOS option is not saved in the BIOS. It is for this reason that every time the system is turned on, it is being reset to zero. When such a situation arises normally messages of wrong configuration appear. In such a situation, it is required to change the CMOS battery of the motherboard. It is also required to select the option of 'Load BIOS Defaults' in the BIOS.


I have had a problem for almost a week. Each time I boot my desktop computer, it is asking me to press F1 to start the system.


I think the battery (CMOS) is dead, and the options in your BIOS are not saved. It is therefore reset to zero each time you shut down your computer.

You will normally get a message like: wrong setting or configuration, press F1 to continue or esc ....
return ......

Change the CMOS battery and in the BIOS select "Load Bios Defaults".

For more information read this FAQ:[ Replacing the battery of your motherboard]

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