if you spread the thermal paste with your finger that was not the best method. many people say that it creates air pockets, and then there are really hot spots that make their way through. if i were you iw ould clean off the cpu and heatsink, and reapply the thermal paste by using the correct method.
most people say the correct method is to put a pea sized amount in center of cpu and then firmly place the heatsink on top so that it spreads it across...there is also the rice method instead of pea...aka, place a very small line instead of very small round dot..some people use an X shape too, but once again--you don't need a lot..i would look for the best method on the arctic silver website. they have methods explained for different cpus.
Instructions for applying Arctic Silver 5..I believe yours would be Phenom™ II X4 With Metal Cap. If that is the right one, then you want to use the middle dot method that they show here:
AMD middle dot method.