malki u posted a photo of your own post suggesting to people to try various combinations of fix1/2 with or without test2.efi.
on a ga-x99-ud4p, I couldn't boot in any combination. with or without these fixes. taken as 1,2 or 3. fix1/2, test2.efi.
system boots fine in efi-32 legacy mode with fix2, but not in full 64 bits UEFI. it boot manager starts, but boots. but fix1 complains about an error that was supposed to be fixed by test2.efi and fix2 gives his usual error.
i will try a new round of tests without the main hard drive that is a pcie drive. intel 750 series. i doubt is the P in x99-ud4P. that only stands for some extra overclocking thingies.
i don't know what's different with mine. i didn't want to convert my drive to gpt, learn about uefi, reinstall windows, figure out how to boot linux in uefi if you don't have a uefi boot environment, but somehow that all worked out just fine. this is one moody os.
what is frustrating is that we have very similar systems. i only have a gtx960, but it's the same generation with your 970. and really shouldn't be that. maybe the monitor edid thing. uhm, i installed the driver from nvidia, but it doesn't work with the usb stick efi32 mode. i think is the 32/64 mode thingie. or some kext from install media that overrides something on the disc. although i used only kexts from lokicat/my own nvme kext. I'll have too look into it.
i had another pci card. one that didn't work in linux either. a sound blaster ZXR. removed that since first tests.
I hope it doesn't turn out to be the hard drive.
http://ark.intel.com/compare/86742,86740
mine i think is the one on the right. the older fatter model.
I expect it to be this, because the test2.efi fix. that could fix some pcie cards bugs, but not others. if i will be able to boot in full uefi 64 without that card of a stick ... then it's that card.
it's enough tests for one day. i'll continue tomorrow.