So, this is weird. I'm trying currently to set up a GRUB dual-boot environment where I can experiment with distros while having Windows 10 as a fallback on my gaming PC.
I've attempted to do a Live USB install of Sarah, latest Cinnamon version, installed with either unetbootin and Rufus on a viable 8GB flash drive. Tried installing on a boot SSD on my desktop both with a Windows 10 installation present and no. Tried launching the installer through the UEFI (default) boot device option and through the USB boot device option which I believe uses a live version of GRUB.
In all cases both with quiet splash enabled and disabled in the boot parameters screen to the best of my ability (even with other distros like ReactOS and Ubuntu mind you) the live USB distribution will render correctly and advance to the point where presumably both the splash screen and non-splash screen boot sequences have finished loading the initial file system and is about to launch the window manager, new installation tutorials, etc.
At that very point the screen goes black (presumably to begin video drivers for the GTX1070 FTW2 (over HDMI) the monitor is driven through) and nothing happens for over 2 minutes. This also occurred with an AMD DualX R9 280X from Sapphire.
Now, I'm not sure whether this is a hardware or software issue exactly, whether I need to retain the " - -" at the end of boot parameters (which is difficult because my USB keyboard always ends up being mapped incorrectly, throwing + and = on backspace, random numbers with numpad and all sorts of nonsense), whether I needed to DBAN my previous Windows 10 installation on this drive or if I'm simply missing something but I find it impossible to install a Linux distribution at this present time due to that black screen issue and I'm at a bit of a loss as far as solutions go. Secure Boot is disabled and always has been. UEFI is used, not a legacy Bios option, not sure where to find that in UEFI yet.
The one thing I have not tried doing is attempting install with my monitor plugged into the motherboard HDMI port which I'd assume would force usage of my i7-3770K's onboard graphics chip set. That said, if I were to install correctly with that, I don't know what that does for me regarding usage of my 1070 down the line, still fairly new to driver management in Linux.
Hardware:
I7-3770K
ASRock z77 Extreme4
EVGA GTX1070 FTW2
Crucial M4
16GB G. SKILL Ripjaws X DDR3-1333
Any advice, including proper placement of this support thread, is greatly appreciated. I'd prefer not having to reinstall Win10 again just to make a new live USB stick and try this again with no guarantee of success. Thanks in advance!

arbayer2