andrej.todosijevic :
Ok so yesterday I built my new PC but a lot of pins are bent and one of them is broken... It's my fault. Can this broken pin somehow be fixed by putting some other pin into the motherboard socket?
Your best hope is it's one of the many redundant pins for power or ground...in which case just plug it in and see if it works.
If you've a microscope, an ultra-fine solder station and extreme patience you could possibly solder a pin on but that's pure hail Mary stuff and if you did you always pose the risk of a weak solder joint breaking, leaving the pin to foul the socket.
You can straighten bent pins fairly easily: I use a .5mm mechanical pencil with the lead retracted. Slip the tip of the pencil over the bent pin and slowly bend it back to straight.
But wait: is this an Intel motherboard with pins in the socket? If so, I think the motherboard is scrap unless the broken and bent pins are redundant or unused. But too many missing redundant ground or power connections can't be good for stability even then.