On trying to install Ubuntu 12.10 Desktop amd64 to a desktop pc using a ga a75 ud4h motherboard (which is using an AMD 3870k APU with a new 1TB HDD) following the advice in the motherboard manual and https://help.ubuntu.com/community/UEFI have now got to grub option screen for EFI install.
Booting live dvd in EFI mode gives "Secure Boot is not enabled" just before grub kernel option list shows.
If the option to "Install Ubuntu" or "Try Ubuntu without installing" is selected gives "can not read cd/0" and "the kernel must be loaded first" errors.
Using DVD or USB installation media gives same results and there has never been at any point an UEFI entry in bios/firmware settings or boot device list/s.
It might be helpful to say that have had an alternative non-linux OS installing EFI mode on this hardware giving a GPT installation automagically using USB installation media when the hdd space was completely unallocated space. The USB device was listed under hard drives in bios/firmware one time boot list and did not have an UEFI entry. i.e. it installed EFI although no EFI or UEFI entry was assigned to the device like what is shown in many tutorials regarding UEFI installs.
Checking md5sum and sha256 checksums on downloaded .iso and used "Check disk for defects" to check burned .iso when booting DVD in BIOS mode. No errors found. "Check disk for defects" will not run (or any other options) when DVD booted in EFI mode.
Due to trying different distributions as well as older and newer flavours of Ubuntu all giving similar results in that no options from grub option screen in EFI mode are bootable (if getting that far) as well as spending time searching Ubuntu Forums have come to conclusion the firmware on this system is hardcoded to handle Microsoft EFI files only.
Installing BIOS mode and using Boot-Repair to install grub-efi is not a complete solution due to the inability of using installation media EFI mode for recovery and maintenance due to the "you need to load kernel first" and "can not read cd/files" errors as described when trying to boot installation media using EFI.
Secure Boot is not an issue. Using msinfo32 from windows confirms Secure Boot is not supported on this hardware.
How to edit kernel or load kernel for EFI install? = How to EFI install Ubuntu?
PLEASE CONSIDER: This is not a dupe! The linked question that is indicated to having a working answer does not have a working answer to "###How to edit kernel or load kernel for EFI install? = How to EFI install Ubuntu?" therefor the workaround of installing using BIOS then manually install grub-efi without renaming bootloaders which works to get Ubuntu booting using EFI or using boot-repair to do this (and many unnecessary "fixes" if recommended repair is not changed in advanced settings) also works. This goes some way to confirming hardcoding of firmware is not stopping grub the boot manager seeing the vmlinuz.efi files in /casper on DVD. I would like an answer to this so would like this question to be reopened.