If your concerned about what your CPUs temps are and want to make sure that they are maintained in a manor that will not cause harm to the CPU then there are several things that you need to decide on first. This way you can set up your cooling system and controlling software to maintain the temps.
1. Do you want to overclock your CPU for added performance.
2. What will you be using your computer for.
3. How much do you want to spend on cooling your CPU.
4. What brand of processor are you getting or that you already have.
5. What type of case do you have and how many fans does it have.
When you overclock your CPU you are raising the clock speed and adding voltage to the CPU to maintain that clock speed and by doing so you are causing the CPU to produce more heat then normal.
The purpose of the computer also brings into the equation the possibility of more heat by way of stress. A gaming computer will cause the CPU to heat up as well as a photo / video rendering computer.
The budget is important as you may need to add fans to the case or get a higher end CPU Heatsink.
The brand of the processor is important since Intel has been moving to lower temps with each new release and currently offer CPUs that have a TDP of 84w , 77w , 65w with only the highend extreme processors being 130w.
The AMD processors however are all higher with a few at 65w but the others are at 95w, 100w, 125w and their new high end CPUs being 220w.
The case and the fans inside the case determine air flow inside the case and can keep the ambient temp lower with the correct fan placement. One or two 120mm fans in the front, one 120mm fan in the side panel, one 140mm fan at the rear of the case and one or two 120mm fans in the top of the case will provide superior case air flow.
Setting up the cooling and air flow.
With the 5 points above addressed you are now ready to set your computer up for temp management.
a. you have chosen the CPU cooler.
b. You have chosen the monitoring programs.
c. Identified the CPU and the temps it produces.
d. Addressed the case and fans needed o provide proper air flow.
Step 1. Using the thermal compound tutorial that can be found in the tutorial section, apply the proper amount of a high quality thermal compound.
Then attach the heat sink, going with an after market heat sink is preferred since the stock heat sink is not very good at higher temps and you need some reserve cooling power in case the temps increase.
Step 2. Install your monitoring programs that will display the current temps and / or one that will control fan speed. The fans will want to be connected to the motherboard if using speedfan and if using a fan controller the fans and temp probes will be connected to the fan controller.
There are a number of fan controllers that fit in the front 5.25 bay of the case and will monitor temps and fan speeds.
Step 3. Using the installed programs or fan controller you will need to set the temp target that you want to achieve and have the program or controller maintain that temp.
It is important to note here that your decisions on heat sink purchase, computer use and selection of thermal compound and application are extremely important to be able to maintain optimal CPU temps. It may be a good idea to get a heat sink that is 25% more capable so that it can easily dissipate any extra eat.
Thermal compound is also important and there are a lot to choose from, do some research and read the feedback to get the best available.
Case fans are the least expensive option and having enough case fans to provide a good air flow is important and should not be overlooked.