Computer shuts off 2 seconds after turning it on.

I was plugging my computer into the power strip the other day. I admit, I didn't perfectly go straight down into the slots on the first attempt (I wasn't forcing it in, more like put the prongs in and they were slightly tilted, so I maneuvered then a little till it fit properly). When I did this, I heard a couple sparks before it finally was inserted properly. I hit the power button and nothing happens. This has happened before, so I unplug it for about 5 minutes

When I boot it up, the fans will spin and the lights come on, but after about 2 seconds the computer shut off and won't turn back on unless I unplug it for 5-10 minutes.

I've tried using a different power cord and even plugged it into a different power strip in a different room. I'm hoping that since it will power on for a few seconds that I didn't blow the PSU.

Any suggestions on i there is a way to check if the PSU is working properly? It's an 850W Xion Powerreal