PC beeps 3 times and won’t boot up!

I just bought a new graphics card (Zotac 1060 AMP) and a new PSU (cooler master 550W). I inserted all the cables in place and placed the graphics card in the slot and connected it to the PSU and now the PC won’t boot up. I did remove the new graphics card and inserted the new one, and it worked fine like it always did. And then I tried to uninstall the old AMD driver and insert the new card, no difference, still won’t boot up.