I had this issue for quite a while now. Whenever I touch the case I get zapped. Everytime it happens I assume it’s a problem with my pc, as it was the first time I built one myself, so I check everything questionable inside, like slightly loose connections and hanging cables. It is then fine for a while, but in a week or 2 it comes back. I did remember having a similar issue while I was using an iMac, when it was plugged into a surge protector. However I don’t think it’s an issue with that, because my pc worked totally fine, without trying to electrocute me for a few months, all with the surge protector.
List of what I did to fix it, from the first time to latest:
1. Unplug reset switch
2. Tie up loose unused cables in back
3. Pushing in the 24pin as far as it goes
4. Unplug unused hard drive, that was powered by a very questionably bent daisy chain cable
5. Unplug barely used shitty speakers
Maybe there’s a few more, can’t remember.