My 1080SC just out of the blue started doing this, the LED on my card will flashing on and off but I get no monitor output to either display port or hdmi, I've tried other cables, I've even tried another power supply, same results. Any ideas what it could be? I did do the firmware update about a week ago but that went fine.

Tried my 980ti in the PC and it works fine....did my 1080 die so abruptly?

Power supply is EVGA super nova 1000 g1 80+ gold
CPU I7 6700k
Gigabyte z170 mb
Corsair 32gig ddr4
Crucial 240gig ssd
Wd 4tb
Win7 x64
Latest GeForce driver
Nothing was ever overclocked

If your GTX-980 ti works fine in the same PC I would have to say with some confidence that your 1080 SC has passed away and needs to be replaced via the RMA process. I am guessing you did the normal checks for a video board like making certain that the power connections are firmly seated and the board is securely positioned in the PCI-E slot on the motherboard?

Yes it's seated fine, it does exact same thing in my other PC, I'm pretty sure it kicked the bucket

You've been very thorough with your troubleshooting. Congratulations for doing a fine job. Starting the RMA process is fairly easy and turn around time is normally less than two weeks. Good luck hoping you get a really decent replacement that serves you well for a long time to come. It's sad to see a high quality video board die so young but these things happen.

Yeah I'm kind of bummed about it, guess I'll be playing Battleground on my 980ti, not like that's bad but the 1080 is amazing, especially at 4K.

The 980 ti isn't a slouch either. I don't know about 4k though. I was just about to pounce on a 55" 4k UHDTV from Sam's Club with only 2 left in stock but by the time I logged into my account they were gone! IDK if they will get more or not but I am really bummed for some reason. I can probably get a better deal on Black Friday anyway. I only game in 1080p 144 Hz which is plenty for my aging eyesight.