I've went for the 1070 and more than happy with it. But I use it for 4k gaming. If you want to play on 1080p then the 1060 is more than enough for modern games.

Also, how does someone clean the inside of the pc with water? All you need is a vacuum cleaner and a soft brush.

1060/Rx 480
either one

that cpu is really old though and going to hold you back and really doesnt have any worth while upgrade options

LTTP: For 350€ I've bought an used 980 ti in august.

Phenom 2 6core !? Your pc stand long use.
I recommend Rx 470 4GB or GTX 1060 3GB .

Was she cleaning your computer with water or just had water near when she spilt it? Because she should have just used some air dust spray.

I'd go with the RX 480 but that is personal bias because I've never owned a Nvidia before.  One thing you should question is if you have enough space and the dimensions fit considering you have a small case.  My old GPU barely fits into my small case and space is one of my main concerns with my next card considering the current barely fits.  I'm probably going to go RX 480 if it can fit into my current case and then in future build a computer that isn't so limited on space.

Yes is been used since 2011 with the overclocking it works like new, I never OC my CPU and well the 3gb version of the 1060 is slower and not just that, 3gb is really no enoguht for some games. I am liking the results is one of the best cards for the price!