Hi I have a really weak barely niticable electric current over my case. I can only feel it on the back of the case (not on the top or the sides) and where it is a small scratch on the paint. I can't feel it with my hand only if I rub my lips I can feel a small tickling ont that's only when the pc is plugged in if I turn of my PSU I can still feel it. I noticed this more than a year from now and the pc runs fine but should I be worried by this?
You should definitely be concerned, it means that your PC is not grounded. I recommend that you plug it into a grounded outlet or install one if you don't have any. It's very risky to run it like this, especially since you could shock yourself or you could damage sensitive hardware.