Oh my goodness..... That's very dangerous. Never ever plug anything into a computer without powering down. This is not an Atari 2600. Bad things can happen if all of a sudden there is a load where there wasn't one before, or you plug in incorrectly and short something. Do yourself a favor and learn how your Bios works. At the very least read the manual. The last thing you need is a corrupt HDD AND a fried Mobo.

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