Did you remove the check in IC?

There is a new checkbox in the render settings.
Leave it checked for normal renders.
If you have artifacts, then remove the check, but render times increase.
Show you render settings please.
For normal renders, I have not seen slow dows.

Poser 1, 2, 3, 4, 5, 7, P8 and PPro2010, P9 and PP2012, P10 and PP2014 Game Dev
"Do not drive faster then your angel can fly"!