45C is quite cool (only 113F).  Generally, those processors are designed to operate up to 70C (my laptop fan doesn't even come on until the CPU gets up near 70C).  Your  fan should ramp up if the CPU gets hot enough.

Peter

45C is quite a good temperature. You should be aiming to keep it under 60C at idle (no CPU activity), and under 80C at full load. Once you get over that though, it gets hot. The max it will get to is probably 95C, and if it hits that it will automatically shut off. So don't be worried about melting it.