I can't tell where that sound is coming from, only you can investigate that.
That psu being a split rail and your mix of parts is not a good match.
Shop around for a 550/600w single rail unit.
I have recently upgraded from gtx 960 to a rx 480 . For last couple of weeks both the gpus are making some kind of sparking noise while playing games and the gpu usage is as low as 50-75%. It's not a cpu bottleneck cause I got an i5 4590 (70-80% while gaming)and 8 gigs of rams. The sparking sound is making me so nervous. Is this a psu issue? I have a low quality psu -Thrlermaltake litepower 450watt. Any info and help will be highly appreciated.