Nvidia GTS 250 does not screen

hello! my video card does not work ( or what?)... I had my PC to tech... and there it was running fine,I played over 2-3 hours, and when I got my PC home it doesn't works, when I plugged monitor adapter in video card,screen just black(power save mode and then black)..I tried everything but not helped.. then I plugged monitor adapter in other plug( I think processor's) and there it works fine, when I am trying to set display drivers It cant..now Im using intel hd graphics, but video card do not responding( it works, cooler is working too, but not display). I do not know what to do.. please help brothers and sorry for my bad english,I hope u understand what I am saying  ...