Note: Different models of BIOS will be different. There are three kinds of BIOS, which you can set according to your own BIOS.
BIOS setting method 1:
When the computer is restarted or turned on, that is, when the Dell or Alienwarelogo is displayed, press F2 continuously to Enter the Bios, press the keyboard arrow keys to switch to the advanced tab, move and press Enter to select the SupportAssistSystemResolution item;
Enter, change SupportAssistOSRecovery to Enabled, then press F 10, select Yes, exit and save Bios settings;
When the computer is restarted or turned on, that is, when the Dell or Alienwarelogo logo is displayed, press F 12 continuously to enter the boot menu, and the SupportAssistOSRecovery option should appear.
BIOS setting method 2:
When the computer is restarted or turned on, that is, when the Dell or Alienwarelogo is displayed, press F2 continuously to enter the Bios, expand SupportAssistSystemResolution, and click SupportAssistOSRecovery；;
Check the check box on the right, click the Apply button at the bottom, and click OK in the pop-up window to save the settings;
Finally, click Exit at the bottom to exit the Bios, and press F 12 continuously during the computer restart to enter the boot menu, and the SupportAssistOSRecovery option should appear.
BIOS Setup Method 3 (Latest BIOS)
Some Yue Ling and XPS models have installed the new Bios. You can turn on the SupportAssistOSRecovery option by doing the following;
The above is the detailed method to find the lost recovery startup menu in Dell laptop. You can find it according to the above method. You can try it.