The BIOS resets to its default settings when ?
When the BIOS changes to default settings??? Will it change back to default after changing processor??? Will it change back to default when I will change motherboard???? Or it will set back to default when I change hard drive?
There are only two times a BIOS will reset to default settings:
1. You reset it, either using a jumper or reset option in the BIOS settings.
2. The backup battery dies.
Since the BIOS is part of the motherboard and has its own backup battery, it will not reset by just removing power from the motherboard.
As cklaubur is pointing out, the BIOS settings are stored on a chip that is a part of every motherboard, and the settings are retained in that chip's memory by a small, replaceable (normally), button-cell battery. Wherever the motherboard goes, so go your BIOS settings. If you install a new motherboard into your computer, it will have it's own BIOS settings that you will want to ensure are correct when you go to configure the system.