[SOLVED] Brand New PC keeps crashing

[dah.who.now]

I recently built my first PC, which is great. BUT, after I put any kind of load on it it will crash and then not start up. It will still post and try to start, and I can access the BIOS menu. Resetting the whole thing is the only fix I have found that will get it to start again, but then of course I have to go through that whole process and it will still crash after a bit.
I have tried flashing the BIOS, which helped, but it still crashed after a few hours. Power cycling didn't help either, dismounting the RAM was also suggested and that didn't fix anything either.
A few people have suggested that this might be a PSU or MoBo issue, how would I go about figuring that out?
https://pcpartpicker.com/list/Tzxk3b
I haven't gotten a GPU yet since the CPU has on-board graphics.

 

[SubaruWRX244]

What is the blue screen error the computer is giving you . All those parts you listed are very good quality and would be surprised to see one broken .
1. Can you monitor your temperatures in the bios?
2 Does the computer just completely shut down like a power outage? If this applies then its likely you have a bad PSU.

Purchase a PSU Here: https://www.evga.com/products/productlist.aspx?type=8 $19.99
It's a cheap tester, however I'd recommend an RMA on the SeaSonic unit. This is one of the simplest ways to test this.