Most computers actually contain what is essentially a miniature Quartz watch inside them that is powered by a battery. This is evident in the BIOS (or UEFI in more modern computers) since the clock still ticks without the network. Without power, it continues to tick due to the CMOS battery, again evident by booting into the BIOS/UEFI. When you do end up getting internet, it'll recalibrate itself with a server, all the while with the miniature Quartz watch still ticking.
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Most computers actually contain what is essentially a miniature Quartz watch inside them that is powered by the CMOS battery. This is evident in the BIOS (or UEFI in more modern computers) since the clock still ticks without the network. Without power, it continues to tick due to the CMOS battery, again evident by booting into the BIOS/UEFI. When you do end up getting internet, it'll recalibrate itself with a server, all the while with the miniature Quartz watch still ticking.
Most computers actually contain what is essentially a miniature Quartz watch inside them that is powered by a battery. This is evident in the BIOS (or UEFI in more modern computers) since the clock still ticks without the network. Without power, it continues to tick due to the CMOS battery, again evident by booting into the BIOS/UEFI. When you do end up getting internet, it'll recalibrate itself with a server, all the while with the miniature Quartz watch still ticking.