how do I find out what graphics card I have?

I'm on a public computer, and I want to know what the graphics card is that they are using.  How do I go into system settings and find it?

>>2
why do you want to know?

anyway, on the back of this computer is an extra-wide female monitor jack.  Plugged into this is a thing that then splits into two monitor ports.  I'm wondering what kind of graphics card this is, because I wanna find out what graphics cards have such a wierd connector.  I don't want to be pointed to links of graphics cards with double monitor connections, I want to be pointed to the procedure that lets me find out what graphics card is on this computer.

Plus, I'm running around trying to fix/upgrade friend's computers, and I need to know what graphics cards they have.