Monsoon II Lite: Thermal Electric Cooling Tower

How the Monsoon II Lite Works

Thermal Electric Cooling is based on a very simple concept. When a low voltage DC current is applied to the junction of two connected dissimilar materials, heat can be moved from one material to the other. One side is cooled (cold plate) and the other side is simultaneously heated (hot side). The temperature differential between the sides can be upwards of 50°C, and the heatpipe/fins arrangement enhances cooling by creating a temperature differential that can be moved out of the system.


You may wonder why this simple concept is not used in every cooling device. It is because things are not as straightforward as they first appear. The cooling process itself is very inefficient, and the Peltier consumes more power than it produces in cooling. In fact it consumes two or three times more power than it delivers in cooling. Another major issue is that during idle and light loads the cool plate and the area around it may suffer from condensation and frost may form. This is one of the reasons phase-change cooling devices are heavily insulated (and expensive).

Another problem that needs to be addressed is the proper sizing of the TEC. If it is too small (low-wattage) it won't be able to keep up with the CPU heat generation; too large and it could rapidly overcool and frost over. Solid state devices like a TEC are very reliable, but another overriding concern is that if anything goes wrong, such as lost power to the Peltier or a broken wire, the Peltier stops pumping heat and becomes an insulator, which could cause a processor failure with no other cooling available.


Vigor believes they have eliminated these problems by combining a medium-power intermittent TEC with an efficient heatpipe cooling tower. The Monsoon II Lite isn't designed for extreme sub-zero overclocking. Instead it is designed as a high-performance Heatsink/Fan with a 25°C target temperature, which is a little higher than ambient room temperature. By limiting the maximum temperature by intermittent operation of the Peltier problems like condensation are no longer an issue.

In addition, the heatpipes are connected to both the cold and the hot plates. This provides Monsoon II an alternate heat-flow path from the vulnerable cold plate, and it protects the processor in the event of TEC failure. Finally, when processor load is light the Monsoon II can switch off the Peltier and simply rely on the heatpipe tower for cooling. When CPU demands are high the Peltier runs almost continuously, and in medium loads the TEC switches between on, half-power, and off to maintain the target temperature.

This hybrid of a TEC and a heatpipe tower will certainly not challenge the cooling of the extreme refrigerated phase-change coolers. However, it does offer the potential to outperform standard air and water cooling. With the Lite priced at $100 or less, it also offers the potential for better processor cooling without breaking the bank. At a street price of $89 the Monsoon II Lite is barely more than some of the top air coolers and cheaper than most of the water-cooling kits.