PC Won't Turn On Randomly

[Cababido]

My PC wont turn on sometimes. It happened for the first time about a month ago, I left the city for 3 days and left it unplugged in case of a power surge, when I came back I plugged it back in but it wouldn't turn on, my headset and mouse did light up tho, so it kindaa threw me off. That same night I started testing every component, mainly RAM, CMOS Battery, PSU, Power Button and MoBo and all of em are fine. The problem still ocurrs to this day, it would act as spected but once every couple days it would not turn on regardless of what I do. What do I do to fix it? Nothing, nothing seems to work reliably. Gotta make clear this happens more often than not when I unplug it or the power goes out, and it is plugged into a Power Surge Protector + UPS. 

 

Specs:

CPU: AMD Ryzen 5 3600XT
Motherboard: Gigabyte B450M DS3H
Memory: Corsair Vengeance LPX 16 GB (2 x 8 GB) DDR4-3200 
Video Card: XFX Radeon RX 570 4 G
Case: Cooler Master MasterBox Q300L MicroATX
Power Supply: Thermaltake Smart 500 W 80+

[Skiiwee29]

My guess would be the PSU. Its very weak and not recommended for any systems other than iGPUs due to its numerous issues and problems. I would buy a better PSU and it likely will clear your problems. 

[Cababido]

Welp, Ive just changed my PSU to a thermaltake 650w 80+ bronze one and it still does the same, any suggestions??? As I said it turns on randomly, whenever it feels like responding to the push of the power button.