Reinstalling or restoring the operating system, checking and treating a computer for viruses, or loading any specialized program from a CD / DVD disc requires setting the boot sequence in the computer's basic program (BIOS).
Most computers, after configuring the operating system, are set to boot, first of all, from the main hard drive. This is done on purpose, since the user can leave a CD / DVD disc in the drive or an unplugged flash drive, which can lead to an attempt to boot from removable media. But if there is a need to boot from an optical disk, then you need to change the BIOS settings.
How to enter BIOS
To enter the BIOS, when you start the computer, you need to press a hotkey within a strictly defined time frame. The most common case is the use of Delete, somewhat less often F2, but there may be others. In any case, at startup, the system shows a set of hot keys for several seconds, where you can find out which one should be pressed.
Configuring Boot from DVD Drive
Most computers in use have a standard BIOS that is controlled only by the keyboard. But new computers already come with a basic program graphical interface (UEFI BIOS), where you can use a mouse in addition to the keyboard. In general, the configuration of both versions is similar, only the control is different.
Further steps differ slightly depending on the manufacturer (indicated in the topmost line). In Award BIOS, open the Advanced BIOS Features section, then in the First boot device item, install the CD-ROM (to select, use the Enter key, and a list will appear). Once selected, press Esc, select Save & Exit Setup and press Y.
In the AMI BIOS, go to the Boot section, then to Boot Device Priority, then in the 1st Boot Device subsection, install your optical drive (the device model is displayed). Then exit the Boot subsection using the Esc key and go to Exit. Select Ext & Save Changes and press Enter.
In Phoenix Bios, open the Advanced submenu, then in the First boot device item, install the CD-ROM (to select, use the Enter key, after pressing which a list will appear). Then press Esc and go to Exit. Next select Save & Exit Setup and press Y.
After completing the steps above, your computer will always try to boot from optical media. If there is no disk in the device, then the boot will be performed in the usual manner, that is, the settings can not be changed back.
Alternative way
In the case of a one-time need to boot from CD / DVD for most PCs, at startup, you can choose to boot from a different drive, relative to the one set in the settings. To do this, at the time of launch, you must press F8 or F12 (displayed at the start of the system in the list of hot keys).
