So I’ve had my FTW3 ultra for around a month and haven't changed drivers in a few weeks, I haven’t had any significant crashing/stability issues until today when my Z73 AIO which displays my CPU and GPU temps suddenly showed my gpu at 0 degrees, followed by a black screen and the fans ramping up to 100%. The power LEDS do not light up red (I have a 1000 watt EVGA PSU...) the computer posts fine and I can get to my windows desktop for a few seconds before the problem recurs... I’m very disheartened and don’t know if this is a hardware or software issue, looking for suggestions...
 
UPDATE - Card seems to be working again, seems like a software issue...
UPDATE 2 - Not stable still continuing to crash as described before... I was overly optimistic. Is this a lemon or is the software causing problems? Does anyone know? 

Baptisten
I had this issue with my gigabyte 3090 card. Since 3 weeks, randomly while playing games the screens go black and gpu fans go to 100%. Power button reset fix it and it posts fine. I turned in my gpu today for RMA.

I'd be interested to hear how your replacement card fares in comparison.

The sad/funny part is this is already a replacement card. My first gigabyte 3090 died 1 month after i received it... 
 
Edit: The first GPU died in a different way, without showing these issues. It just randomly crashed during a game session and PC ouldnt boot with it installed.