Managing your fan speed won't help you in this case. When the CPU is running FULL speed (rendering a video, for example) it's also producing the maximal amount of heat and as the temperature rises, the fans end up running full speed too. Any sustained 100% load soon (in a minute or so) brings the fans to their max RPM and the temperature stabilizes at a certain point and you can't make that point lower by any software.
A cooling pad can help you if you do this often and you don't want to stress the system too much or if you really don't like the sound, but if the machine is clean inside and nothing restricts the air flow, it's capable of cooling itself.