Are you using a surge protecter/suppressor? If so, I would change that. I would also open the box and reseat the power cords that run from the power supply to the motherboard. You can also change the power cord, its cheaper and easier than changing the power supply. If you do change the power supply, make sure its the same wattage. There is that little switch on the back of it.
I never get shocked cause I'm always grounded!!
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