Guys, I was just installing a new ram, I tried removing the old ram but it cant be removed so I apply pressure to the old ram to check if it was loose, after that I just put my new ram beside the old ram , when I put the power cord and start my pc, the computer turns on but no display, so I removed the power cord, opened the case, removed the new ram and put on the power cord and started my pc. When I started my pc it started but again no display from monitor