Install UEFI Windows 8 – DVD vs USB Guide

EFI implementations must provide some way to control the boot mode (EFI vs. BIOS), except of course for EFI-only implementations without BIOS support. Too often, though, the firmware gives the user little or no explicit control of the matter; instead, the firmware attempts to infer the correct boot mode based on the state of the hard disk -- for instance, it might use EFI mode if a GPT is detected and BIOS mode if an MBR is found; or it might use EFI mode if an EFI System Partition (ESP) is found and BIOS mode if not. You may be able to find a clue about what your firmware is doing by reading the manual. If not, you'll just have to experiment.

When booting removable media, the rules may be different, but you can often give it a kick in the right direction by providing just one boot mode. This may require re-mastering a CD or (more easily) carefully selecting a CD. If you're trying to force an EFI-mode boot, my rEFInd, and in particular its bootable CD version, may be helpful; it boots only in EFI mode, and as configured, it will act as a boot manager for other EFI-based boots, but not for BIOS-mode boots.

Windows 7 doesn't support the new UEFI GOP (Graphics Output Protocol) and requires VGA option ROM (BIOS interrupt 10 (INT 10H)). Win8/10 supports GOP and reads the UEFI Logo and displays it during boot for a smoother boot. And it seems that your UEFI always turns GOP on and disables VGA, so Win7 can't be used and hangs at Starting Windows with the graphic artifacts.