The problem could be a combination of four things (others may suggest more):
1) If you're using a "pea"-sized amount of TIM, you're using way too much. Depending on what compound it is, 1-2 grains of rice is more like it. I'd look up application stories from folks who have used the same compound to see what's worked for them.
2) The cold plate may not be seated properly. The first time I installed an H50, I though it was seated as well as could be, but it was actually barely making contact.
3) If everything is at stock and you haven't changed any settings, then your voltages are too high. High voltages will generate more heat.
4) The 3570k is put together...poorly. Instead of the IHS being soldered to the die as was the case with the 2500k, it's glued to it with TIM. Many people, after having "delidded" their CPUs, applied TIM properly, and then relidded them, have seen temperatures drop 20-30C.