Hey guys having a pretty serious issue since the latest nvidia driver (471.11) 
Monitor will shut off and say no display detected, pc will still be running and still can hear audio. Graphics card heat is fine and still maintains fan speed. It forces to me turn off my pc. Only happens while gaming. Can do it from 1 minute to 3 hours it’s just random.

I DDU’d all the drivers and went back to previous drivers and still didn’t work. Unplugged all display cables, nothing.  Is this **** bricked?

EVGA XC3 Ultra RTX 3070.

Doesn’t crash at all and temps are fine.

Well hopefully your issue works out better than my experience with something like this did.  I had a 2080 Super Hydro that was great when I first got it.  Then it started to randomly black screen and that just got worse over time.  I never even overclocked it just installed drivers and went.  The black screen was the same deal computer was still running.  It was just like the GPU would vanish.  I think I had like 90 days to enter step up (something like that?) and the black screens probably didn't start until day 50 or 60.
 
For me the solution was to RMA Step-Up to the 3080 I have had since last October.
 
*edit*  I went through all the trouble shooting steps.  Read the threads here about Black Screens and searched for black screen threads.  Complete fresh reinstalls etc Nothing changed the black screens once they started and once they started they got worse very quickly.  At first you could play games maybe for hours and then open a browser and black screen.  Within a few days it would either just constantly black screen or not recover at all.  I've read some threads where people were able to resolve this, but nothing worked for me beyond the RMA.

check the slot , reinstall drivers or maybe put the card in another pc .

Could it be a driver issue?

My english is not perfect !
 
Short story : Was in the same boat, I resolved this by changing an option in Nvidia control panel : below resolutions selection, select Use Nvidia color parameters, if your TV or monitor can handle it, change color output format from RGB to YCbCr444. RGB is taking a lot of bandwidth and YCbCr 4:4:4 compress the signal up to 50% and help HDMI handshaking. After that, turn off your computer and monitor or TV, then turn on you monitor or TV first, then your computer, good luck !
 
Detailed story :  I have an EVGA RTX 3080 XC3 with a Samsung Q90T TV. From the beginning I have a loss of signal which occurs when I start a game or when I turn on the TV after a certain delay. Looks like there is a handshaking problem between the card and the TV. I Also recently experiment black screen in games, I also lose sound after a while and have to turn off and restart the computer. For my part, these problems are only present if the Input Signal Plus is activated on the Samsung, this function allows me to activate HDR and get the resolution of 120fps in 4k (this problem seems to happen anytime, without any reason, sometime it's more stable than other) So I am a bit like everyone else, I try to find a solution and I do some tests. I found something interesting: I changed the output color format in the Nvidia driver, it was at "RGB" and I put "YCbCr 4:4:4". I read that the native RGB format does not have a very compressed signal and knowing that I especially have problems when there is a lot of information to transmit (ex .: 4K 120fps), the 4:4:4 sends data in a different way with less bandwidth and stronger compression (up to 50% less which takes us away from the physical limitations of HDMI and cabling), your monitor or your TV must be compatible otherwise this option will not be available. The TV will then convert it back to RGB by itself for display.  Take note that 4:2:2 or 4:2:0 will produce a lower resolution (than the actual resolution selected) and are less interesting options. Yes it can slightly change the quality of the image, the blacks are stronger, you can compensate by adjustments, but it's a mode which is advantageous for the players. Once the options are done I turned off the PC. Then I turned on my TV first, then the PC to ensure proper signal detection. Following these steps, I am able to play without any problem. The next morning (after a delay where I do not touch the computer anymore), I lost the video signal and no wake up when touching the keyboard or the mouse.  This bug is also weird but using the Windows key + CTRL + SHIFT + B will force a reset of the video driver and will force the handshaking connection of the HDMI and allows the return of the display.  Take note that my Nvidia driver is 471.11.   Also be sure that you have the latest firmware of your TV (my Q90T have been upgraded to version 2016 and the handshaking seems now resolved.
 
Good Luck !