I had an old graphics card that worked but was on its way out performance wise. One day i turned on my pc after using it normally the previous day and now the monitors would display a no signal message. So i assumed my old graphics card had died and i bought a new one. Now this one has the same message and i dont know what to do. Everything powers on and seems to be working otherwise. Also if this helps i originally was using 1 monitor for the lifespan of my pc and recently switched to 2 monitors last month and having 2 monitors worked for about 2 weeks. I don't know if that helps. My specs are as follows:
i5-6500
Gigabyte GA-Z170-HD3P
16GB DDR4 2400 RAM
2TB HDD
250GB SSD
Sapphire pulse RX Vega 55 8GB HDMI2
EVGA 650 W 80+ Gold PSU