Weird grinding noises on PC?

Ok so whenever i start my pc it makes this loud noise im sure its coming from the fan, processor fan, psu or maybe gfx card. i have made sure no wires are touching any parts. Oddly it makes this noise then dissapears for a while only to come back again but even louder. so please help me figure out what is making this noise (by the way my pc is not even a year old and only things i upgraded was gfx card and power sup

ply) this started happening only today but never before. and when the pc makes loud noise it sounds like someone is using a drill. please help. i dont think its my hard drive cuz that is not where the noise is coming from...Videos concerning this:

http://s153.photobucket.com/albums/s228/52massacre/?action=view&current=MOV00994.flv

http://s153.photobucket.com/albums/s228/52massacre/?action=view&current=MOV00995.flv

i kno i asked this Q before but i need more answers bad quality vids so plz make sure to put sound waaay up. thanks in advance.