Question New PC displays no input on monitor, plus keyboard and mouse don’t light up ?

Oct 15, 2020
This is my first build and I haven’t been able to get my PC to display anything. All my plug ins seem to be in the right place and all my fans run and my mobo lights up. I have tried replacing the ram, unplugging and replugging my power chords, resetting my cmos battery, and plugging my hdmi chord into the motherboard as well as gpu. All my parts are new and installed correctly. I’m starting to think it’s a problem with my power supply as my mouse only lights up when clicked and my keyboard won’t light up at all, but I’d expect my screen to at least show the bios. Would really appreciate some suggestions on what to do, thanks.

Parts are
Ryzen 5 3600
GeForce 1660 ti ventus oc
2 8 gigs of Corsair vengeance
Western digital 500 gb nvme
Asus prime b350 plus
H510 mid case
500 watt bronze 80 psu