Poser is quite light on CPU's exept when rendering.
For a render it runs at a full 100%CPU.

So after the render is done the CPU (and fan) should cool and slow down.

There must be some free apps around to check your systems activity and temperatures.

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"!