Sooo my computer randomly shuts down while playing games (rarely when idle) Sometimes it boots back up by itself or it does not. Sometimes it even shuts down while booting. When it doesn't boot if I smash it or move it the leds turn on for a split second. I made sure every cable is connected properly. I have the money for a new psu-Corsair CX650W (I've read that they are good af) and some money for a few more coolers to add in my case. Should I buy the new psu and the coolers or send it in for repair? I already sent it for repair and they reinstalled windows and changed the motherboard and came to the conclusion it's cause by steam. I reinstalled windows with NOTHING on it and it still restarted. If I send it in for repair I might not have money to replace anything. What should I do?

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