CPU Eat 'n' Cool is a simple Windows software designed to limit the temperature of your computer while it is busy, if you want an idle CPU Cooler there are others products for you.
CPU Eat 'n' Cool tries to keep the CPU (and the overall system) cooler while the system is busy. If you are searching for a utility that keeps your CPU cool while your computer is idle this program is NOT for you.
Every modern CPU supports the HLT instruction (opcode F4) that instruct the CPU to enter a stand-by state. Windows operating systems based on NT (like NT 4.0, 2000, XP) calls this instruction during the idle time. But sometimes could be useful to execute this instruction when the CPU is heavy busy, for example when you are playing a game. For example I have a notebook, and when the room's temperature is over 25 C I cannot play a game because the interal case temperature quickly goes over 75 C and the computer powers off itself. I cannot modify the hardware cooling systems of my notebook so I decided to write this program.

CPU Eat 'n' Cool (CpuEnC) 'eat' some CPU power to execute the HLT instruction. Your games or your applications will be a little slower while CpuEnC is active but your CPU will be surely cooler.

CpuEnC works at the maximum priority allowed by the system executing an HLT instruction every few milliseconds. In this way the other programs have less time to perform their task and the CPU have more time to sleep and cool. This means that you can play your favorite game while keeping your CPU cool. Of course, keep in mind that the game's (application's) performance will be affected by the CPU Eat 'n' Cool presence.

This is the basic of CpuEnC: cool means less performance.

This is like a sort of program underclocking.

This is the core of CpuEnC. Changing this parameter you decide how many milliseconds CpuEnC must sleep between two HLT's blocks (to understand the meaning of block see below Boost Factor). To better understand you can imagine this parameter as 'how many HLT's blocks in 1 second?'. 1 second = 1000 milliseconds, so, for example, if you set the Sleeping Time to 20ms you can do 1000ms/20ms = 50 that is the number of HLT's blocks executed in 1 second. More HLT's blocks are executed, more times your CPU will stand-by and cool, but more CPU power is consumed for that task. So smallest values give more cooling but worst perfomance and bigger values give less cooling but better performance. Now it's up to you to find the right value but follows these tips:
1. The room temperature is very important. The same value could lead to different results in different times.
2. There are different type of games and applications. The same value could lead to different results if used with different games or applications.
3. If the CPU is very busy the most sensibles values are from 1ms to 5ms. This means that a very little change could affect consistently the cooling and the performance.

The license of this software is Freeware, you can free download and free use this cpu benchmark software.