[identifying model of cpu cooling fan for replacement or upgrade]

I'm wondering if anyone can help me identify a model number etc on this cpu cooling fan.  it started making a vibrating noise. i have had a couple shut downs and reboots, a couple times happening when i tried to play some sound.  it doesn't seem to be running as fast as it used to.  so i am thinking it might be going bad.  i want to either replace it or upgrade it.  but i am not sure if i am limited to the type of clip that holds the fan in place.  thanks in advance for any help you can provide.