PC randomly switching off and monitor randomly going out of focus

Dylzan

Honorable
Aug 2, 2013
1,238
0
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Just today I've started having 2 weird issues with my PC. Specs are:
i5 3470, MSI GTX770 OC, 8GB Kingston HyperX 1600MHz 1.65v, Corsair RM550 PSU.

My first problem is that my computer randomly shuts down and restarts. I was playing Garry's Mod which isn't an intensive game and my GPU was only about 30% load. I've checked temperatures and they're about 40C on the GPU and the CPU.
A second problem which could possibly be linked is my second monitor, connected via a VGA-DVI adapter, the monitor seems to randomly go in and out of focus for no real reason.

I'd appreciate any advice you may have as its only ever happened today. Thanks in advance.