I need help badly and fast, psu error

[Skrap98]

Hey yall, listen up.
I had a corsair rmx650watt psu working like hell for like 4 months. I had to unplug my pc for a month and when i plugged it back it didnt want to start up. Whenever i turned it on, it would shut down the power of the whole house and sparks would go off the psu. After all i decided to send it back to where i got it from, they said it worked fine for them. Then they said why was that happening. I am dumb enough to connect my psu wrong, i screwed all the screws right expect one, i screwed one screw INSIDE the grid of the psu, that screw was touching the board of the psu and it caused it to shut down and create sparks. I personally think the psu will work fine because its one of the best psu's on the market thank god, it worked fine on him when he tested it (the mechanic) What are your thoughts? Should i reconnect the psu to my pc? Is it safe? If its damaged is it possible to fix it? (I am gonna send it to another mechanic to recheck btw) I am asking because many people here have tons of knowledge on this stuff.

*Pc specs
Mobo:Asus z270 strix
Cpu:Intel i5 7600k kaby lake
Gpu:Amd radeon 4gb 380x
Psu:Corsair rm650x
Case:Thermaltake versa c22
Cpu cooler:Cryorig h7
Ram:Hyper x 8gb 3000mhz

 

[James Mason]

Well, either the system is already dead or it isn't.
You can always paperclip test the PSU to see if it starts up on it's own.
http://www.wikihow.com/Check-a-Power-Supply

 

[Skrap98]

I dont think so.
First of all the psu itself protects the other parts from failure. And when it lastly shut down i saw that the light of the mobo was still on for like 10 more seconds so i dont think that any compoments of the system are fried. All i care about know is the psu, after i get it back from the mechanic we will know. What do you think? (about the psu not the other parts)