A quick search on google shows this is a recurrent issue across different Gigabyte motherboards, and since now many months. This is another drop of post in an ocean of "cannot enter BIOS" on X99 Gigabyte motherboards.
As said in the title, attempting to enter into the BIOS of GA-X99-UD5 WIFI rev 1.0 (currently on F10d BIOS, same issue with other previous BIOS) miserably fails and results in a blank screen.
However, If I unplug all the SATA devices it will successfully enter and display the BIOS, but come on.. opening the case, unplugging SATA, etc.. is not the expected workflow to reach the BIOS, it should just work. I have to mention I also tried converting the FS of my drives to not have any MBR partitions (based on pseudo-solutions i've read on this forum too) and that did not fix anything at all.
Despite the hardware looks pretty great and works, I also have to mention the poor quality of the softwares (SIV, easy tune, etc) bundled with the motherboard, it's unbelievable for some parts, and I'm not sure they are all tested at all.
Example on launching one of the tool: "Error - This Driver can't release to failure!!" < yes, that's a popup message error lol..
Example on Easy tune: Froze the whole OS after selecting a "default provided profile", corrupted the bios values preventing any successful boot into the OS, forcing me to open the case and reaching the BIOS (back to the cannot enter BIOS).
Example on SIV (System Information Viewer): if you let it run for half-an-hour or more, it starts eating more and more resources on your CPU each time it refreshes (periodically), also (not) worth mentioning the chart does not scale well and auto scrolling is.. (sit down).. on a reverse x-axis and is being draw from right to left (at right you have t-1, middle t and left t+1).
Come on Gigabyte, step up your game, your hardware is great but you have to improve your software (BIOS included) drastically!