Ok, I'll replace it with something else. But would the fact that it supports Intel i7 and 5 like it says on the box And my computer has an i3 processor have something to do with it?
No, nothing to do with it.
Also the connectors it comes with has more pins than the original power supply. 20+4 instead of 14
All mothern PSUs have 24 pins. How many pins does your motherboard have? What model is it exactly after all?