[SOLVED] Just assembled PC, won't boot

[Snickerdoodles]

Hey guys, just finished putting my new parts together, however when I turn the PC on the monitor remains black (button glows orange just like when it's off) and my keyboard/mouse don't light up even though they're connected. The CPU, system and GPU fans all work - furthermore, the GPU one spins like crazy (compared to my old setup that is - it used to briefly spin with this intensity for a few seconds on boot, then it would calm down; I assume the high RPM is related to whatever's going on here). I'm also unable to shut the PC down by holding the power button, instead I was forced to flick the PSU switch. I've tried reseating the RAM modules, tried booting with one only, checked all motherboard/PSU connections, but I can't figure out what the deal is. Also, there aren't any beeps or warning sounds when I start it up.

Specs:

Motherboard: ASRock B450 M Pro4
CPU: Ryzen 5 2600x
GPU: Aorus Radeon RX580 8GB
PSU: Seasonic Focus Platinum 650W
RAM: Corsair Vengeance LPX DDR4 2x8GB 3200 MHz

 

[rgd1101]

test breadboarding it?

 

[NightHawkRMX]

https://forums.tomshardware.com/faq...deo-output-troubleshooting-checklist.1575220/

 

[Snickerdoodles]

I've solved the issue - thankfully the only problem was me being stupid, and in checking if all my connections were proper I forgot to check if I had actually connected everything I needed to. I managed to forget the 12V ATX CPU cable. Nevertheless, thank you for the answers.