[SOLVED] Computer runs for 15 seconds, then turns off.

[rlyoung]

Installed a Ryzen 5 3600 cpu, and then turned on my computer. It turned on, cpu and case fans were working, video card had power, yet no display appeared on my monitor (hdmi was plugged in properly ). Additionally, my computer would turn off after running for 15-20 seconds, and would then restart. I reinstalled my old cpu (Ryzen 3 2200g), and my computer wouldn't even turn on. Put the Ryzen 5 3600 back in, and the original issue continued. Could this be an issue with the cpu? An issue with the mobo or psu?

Specs:

CPU: Ryzen 5 3600
Motherboard: Gigabyte B450M DS3H
Video Card: ASRock RX 5500 XT
PSU: Corsair CX 4 W 80+ Bronze
Case: Thermaltake Versa H21 ATX Mid Tower Case
Memory: GSkill Aegis 8GB (2x16 gb) DDR4-3000 CL16

 

[Ralston18]

What wattage is that Corsair PSU? 400, 450, or some other wattage?

Also: PSU age, condition? Any heavy use for gaming, video editing, or even bit-mining?

 

[rlyoung]

450 watt (thought I included that, sorry)
Right at two years old. Used for gaming. Never played anything too intense other than cyberpunk within the past week, and it had no problem with that.

 

[rlyoung]

Update: replaced motherboard with B450 Tomahawk Max, and my rig starting working. So chalking this one up to a bunk mobo.