What are the normal and optimal ranges of CPU temperature for different types of processors?

Many laptops and mobile devices will run their processors closer to 100⁰C and tend to have higher temperatures overall. This is usually to limit how much the fans have to ramp up and down as the load changes.

MSI Afterburner is a very powerful tool for controlling GPU fan, and overclocking the GPU as well as monitoring all temperate sensors / voltages / power usage and frequencies in your computer in a graph or in game overlay format.

It is also helpful to control the ambient temperature that feeds your cooling system. If the room air is to hot it would not help much help much with heat dissipation regardless of the mechanism you have in place.

In some cases you can add more fans to your system. Increasing the airflow will remove more heat from your system. One thing you must consider is the direction of you air flow. ideally you want to balance the amount of cool air being taken in by your system and the amount of hot air being exhausted by your system. You can tell the airflow direction of your fan using the support brackets found on the fan (they hold the motor). The side of the fan that has the brackets is blowing air away from the fan, the side without the brackets is taking in air. Make sure you have sufficient air flow over critical components such as your CPU, RAM, and GPU.

I don't think there needs to be a section on "how to heat your cpu," that makes as much sense as adding more heat to an combustion engine. The "Department of Redundancy Department," write this section?

No such thing as cpu too cold. Your CPU can't be below ambient temperature unless you use active cooling, and if you were using active cooling you're trying to get it below ambient on purpose. Also, smaller case doesn't mean hotter. Big case is worse for airflow sometimes since you want air to be forced near the components not just pass around them in a big case.

Weird. Unplug all fans and run a benchmark utility. This question must have been translated improperly or something. Doesn't make sense.

You need to balance the thermal design power (TDP) of the CPU with the performance you desire. Higher TDP = more generated heat. To dissipate CPU heat, you need good heat sinks, fans, and air flow. You also don't really want your CPU doing graphics processing. Off board that to a good GPU (video card). But again, those generate considerable heat as well. As you can see, system design and parts (where changeable such as desktops/towers) are interdependent (i.e. power supply requirements, etc.). Although CPU temps should remain on the lower half of the recommended operating temperature, remember that they are designed to run well within a range, so don't freak out if they occasionally run hot during increased loads.

High workload can cause poor CPU performance: Running resource-intensive programs or processes can cause your CPU to heat up quickly. This can also be a sign that your computer has been breached and is possibly infected with some form of Malware.