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So it seems it has nothing with the video card at all, here's the vga cable touching directly to the PC case;
(Monitor turned off, power cable of the monitor is plugged)

Wall:

Monitor power cable:

Hot chassis ?

You could try inserting the plug of the AC cable the other way round (rotated) in the wall socket.

Edit: The plug/cable of one device, I mean. Either the monitor or the PC.
If the PC case is hot, try the PC power cord first.

Edit: Or it's the monitor ground, maybe ?

Hm. Another explanation.. There's some weird stuff with the phase happening.
The american appliances do something weird sometimes.
These devices sometimes use 2x 120v to make 240v, if needed.
So if the monitor was built for an international market, originally..
Anyway, it's just a wild guess.

https://de.wikipedia.org/wiki/Einphasen-Dreileiternetz

With an LCD/TFT Monitor that uses an external PSU this shouldn't happen.

This is normal, majority of equipment with switching power supplies have two capacitors connecting mains input to the ground of the device and this makes the ground float at half mains voltage. Normally this is not a problem as you use an earthed socket, but when you don't this voltage goes nowhere and you have it in the chassis. Most unfortunate thing is when it is done on unearthed power supplies such as ones of many laptops...

The big implication of this is that you can actually damage the things being plugged when they already are not on the same potential (i.e through a power strip) as that 115V or so is capable of destroying chips even though current is very low. You can also get shocked slightly when you ace in contact of one device that is earthed and connecting another that is yet to be... Very refreshing....

PC cases are designed to be properly earthed (grounded). There's a filter cap between live and ground lines and the latter is connected to your case. That wall outlet does not have an earth connection (looks like one common in NL prior to 1997 update of NEN1010 wiring standard). If you connect the PC to that outlet, your PC's ground line isn't earthed and the capacitor acts like a voltage divider, so you get 1/2 of mains voltage (i.e. ~115V) on the case. If you're connected to ground, whenever you touch the case, it will try to ground itself through you, or through that screwdriver that lights up. Fortunately no significant current can flow through that cap, so it's not physically dangerous but 115V is more than enough to mess with electronics, including (as I can say from experience) the ability to blow fuses behind things like HDMI and VGA connectors.

So TLDR: never run a device designed to be connected to an earthed (grounded) socket from one that isn't.

Edit: Tiido beat me to it 😉

It seems the matter can be very complicated.

- The protective earth is missing in old installations, for example.
Not good for a FI switch / RCD breaker.

- The simple voltage checker can give false results.
https://www.sanier.de/elektroinstallation/ele … richtig-pruefen

- Sometimes, the connection for protective ground is there but messed up. Bent pins, broken wall sockets etc.

*sigh* Why can't electricians do their job properly ?

As the above.

Assuming there's a ground rail prepared in your fuse box, it's not a very complicated operation to upgrade to grounded outlets though. Basically it's just a question of routing a third wire and connect it in both ends (in practice all wires will be replaced, which is a good thing if the wiring is old, the insulation age). Of course I can't recommend you to do it yourself, but it's a quickie for an electrician, especially if you can help him. It's a lot easier doing it with one person in each end of the wire, one pulling, the other feeding. Also, you can do some time saving preparation by mapping the mains network in your house, finding and exposing junction boxes, etc. They're often hidden behind wallpaper, furniture, etc.

Would recommend doing a full upgrade of all outlets in your house while you're at it, but you will at least have to replace all ungrounded outlets in the same room. Mixing your old ungrounded outlets with grounded ones is outright dangerous, since it's possible to connect grounded schuko plugs to them. Let's say you kept your PC connected to an ungrounded outlet, and something else with a grounded shell right besides connected to a grounded outlet. If you touch both simultaneously, you become a path for those 115 volts to ground, and that's going to be way more unpleasant than the minimal currents caused by you being a capacitor you've probably already experienced. Now imagine if that was full mains voltage due to a fault instead...