Make new HP windows 8.1 system bootable from CD

New HP Windows 8.1 64 bit systems can be made bootable from DVD so that we can install windows 7. We have to change following settings in BIOS.

Step  1: Switch on system and press F10 while boot, Now BIOS options will come
         2: Computer setup->security->secure boot config->legacy support->enable
         3:  Device config-> CDROM
         4:  Storage->boot order->UEFI->Disable
                                                 Legacy Boot Sources-> Enable

Save changes and restart.
Now the system is ready to boot from DVD so that you can install windows 7 32 bit also.
If you install windows 7, LAN driver will not be updated. Download LAN driver for Realtek pcie gbe family controller.