My Graphics card gives no signal to the monitor even though it used to work before

[XxTheAMDPOWERxX]

Hello everyone so my mobo has 2 graphics cards AMD Rx 470 which i recently bought from like 2 weeks ago.

Today something happened i don't know what it is actually as i was leaving my computer opened normally and display were off, when i tried to turn my display on from idle mode by moving my mouse nothing happened computer working and everything but no display so i forced closed it and when i restarted it, one of my 2 cards were not showing on windows device manager even though the card is working and fans are spinning normally !!

I installed AMD drivers again with nothing but one card only showing up and working, i closed my computer and removed the working card, put the other one into its PCI-E slot and connected the same 8-bin Power cord of the other card then i restarted my computer but my screen is idle with no display signal !!

Any suggestions what could it be ??
or did this card died for some reason and maybe i need to replace it ?

Help me pls :/

 

[ErikMcLeod]

Do you have enough wattage to power your system? What PSU do you have? Did you accidentally zap any PC components with static charge while the case was open? Did a thunderstorm come through and possible flicker your power while your PC wasn't hooked up to a surge protector?

 

[XxTheAMDPOWERxX]

@ErikMcleod No thunderstorm or flicking in electricity at all, it all happened in front me i forced closed my computer then restarted it normally.

My PSU is 1000 watt HEC Cougar

 

[XxTheAMDPOWERxX]

Alright so i returned my card & it turned out that it really was some issue in the card itself and they sent me a new one