Computer Random Shutdowns

Hello. I have recently reinstalled Windows to try and solve this problem as I thought it might've been the OS. But my computer as of the last month has been randomly shutting down unprompted, and its not a safe shutdown either, it is like a power-loss shutdown, everything just cuts out suddenly. It does this at random, sometimes it runs fine for hours and others it just keeps doing this, any advice or help?

Work through Troubleshooting Steps for Windows 7 to test the hardware, gather clues from system resources to try to pinpoint the cause(s).

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