Reseat all the parts and connectors.
Leave the cpu alone but do inspect the mounting of the hsf.
Try a different gpu in your machine or your gpu in a different machine.
All worked fine for 1 year
Running dual boot win 8.1 and ubuntu 16.
With
Nvidia GTX 1070 connected via DP
Motherboard Gigabyte GA-X99-UD4P
I moved my tower (long ride, vibrations, no shock)
Now
Grub Menu Displays (Initial Display output is on PCIe slot)
I choose the boot option, got to purple preloading screen
Then,
~4/5 times no signal detected by the screen.
Though instance is running, GC fans are spinning, everything looks fine.
Have to force shut down
~1/5 times signal get detected,
potentially need to reboot via win8.1 suggestion according to the fact I forced shut down.
Eventually got a running computer.
Extra tips:
when OS is waked up from sleep, no display;
when display wakes up form sleep, display ok.
when removing the GTX and booting while vga connected to motherboard, all fine
What I did:
Hardware --> take GC out, blow out potential dust from connectors and PCIe slot.
Software --> Made sure Drivers are up to date.
I'm pretty annoyed that I need to force shut down PC ~4 times for it to finally run, as it damages it and takes me time.
Any help on this matter will be highly appreciated, I remain available for any further needed information.

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