The stock cooler that comes with the Phenom II's is pretty good.
3/4ths of this video is the guy opening the box, talk about over dramatic, or they just plain wanted to be annoying, but anyway at the end of the clip they give you a good look at the heatsink.
http://www.youtube.com/watch?v=PE-NnJsv5xY
Oh yeah, I'll pile it on you too. P4 and a 5800 series GPU, now that is just too funny.
Hold on, yeah you are in for a big surprise when you get the Phenom running.
But it's not just the GPU, that Phenom II is literally 2-3 times faster than the old P4 you had, at EVERYTHING.