No UEFI option in bios acer predator g3-605-ur20, I want to install windows 7 Instead of Windows 8.

Step 1:

Turn on Computer and press Del on keyboard.

Step 2:

Use right arrow key and toggle to Boot Options, 1st option is: Launch CSM and it is highlighted. The default is NEVER. Press your Enter Key on the keyboard and change it to Always. Then toggle down to Boot Menu; press Enter Key and change to enabled

Step 3:

Left toggle to the Advanced Tab, then down toggle to Integrated Peripherals. Press Enter after it highlights. Toggle down to Onboard SATA mode, press enter, and change to: Native IDE.

Step 4:

Left toggle back to Authentication Tab; down toggle to Secure Boot; press Enter Key; change to Disabled.

Step 5:

Press F10, Save and Exit. As Computer reboots, Press Del again to Settings. Right Toggle to Boot Options; Down Toggle to 1st Boot Device, change it to your DVD\CD ROM, 2nd Boot Device will be your Hard Drive, 3rd & 4th can be anything by default.

Step 6:

Toggle down to Hard Disk Drive Priority; press Enter, Change 1st Boot Device from the Kingston Drive to the actual Hard Drive.

Solved:

You can now load from Windows 7 DVD instead of Windows 8. And you will not receive the No Bootable Device.