high rpm problem

My 3k's been making an odd screeching, or grinding noise when I hit higher rpms. The problem only happens after 4 or 5k rpms and it doesn't happen all the time. Sometimes the screeching is real loud and sometimes it doesn't happen at all. It sounds like it's coming from the front end of the car near the breaks or front axle. Can anyone help me figure out what's causing it?

if its from the drivers side i would bet its a pully or belt.