I have just encountered the exact same problem, did you get it fixed?
@ronintexas Although what you say is good advice, 5ix has already stated the he has reimaged windows to no avail.
I am a pro user and can't get this fixed. I too have done all the usual troubleshooting techniques from the basics of unplug/replug cycling, reseating ram and only using one stick, running disk checks and memtests, reseating the GPU, different cables and monitors etc right through to downgrading my bios (as I remembered there was a recent update) and attempted various downgraded versions of the Nvidia drivers.
The old fix for this issue would be where the bios or driver would force the on-board graphics to become default so just changing it to the pci slot in bios or in control panel/screen resolution would force output through the GPU. This can also occur when multi-screening or changing between port types i.e. hdmi, dvi, vga etc
No chance of that in my case as there is no on-board graphics output at all.
To my displeasure I am leaning towards a GPU fault as output is fine at a native resolution whilst installing and configuring windows but as soon as the nvidia drivers are installed 'No Signal' is shown, indicating a problem pushing a higher resolution. This includes straight from a clean install and attempting the GPU driver before anything else.
I have had this exact setup running for months, fault free, in 4K and getting decent fps on ultra settings without ever overclocking. I have a 980 gtx on win 10 but have even tried it on win 8 and 7 with no luck.
The only thing I am yet to try is the displayport over the hdmi in case either the port has broken or there is an hdmi handshake issue, unlikely, but I have a dp cable coming soon to try.
If/when this doesn't work I'll be stripping down my build and breadboarding it to see if anything has been fried.