Optiolex3080 turns on the traditional boot.

The traditional startup mode is as follows:

Step 1: Boot F2 into the bios setup interface, find Securebootable in the SecureBoot directory, then select Disable on the right, and then select Apply below.

Step 2: enter the general directory, and then find the following BootSequence option, and the boot option option is on the right. Check all options, and then select the traditional option below.

Step 3: Enter the Advancedbootoptions option and check all on the right. I only have one here. If there are two, please check two. In short, check all, then select Apply and click Exit to exit.

Note: If you get any error prompt in the above operation, enter Restoresettings. If Biosdefault was originally selected, it will be changed to Customusersettings. If the following was originally selected, select the above, and then click ok to continue the above operation.

Step 4: Insert the startup USB flash drive, press F 12 to restart the computer, and then select USB to start.