Chronicle of the development of CPU radiators

Mr. Lu Xun once said: CPUs did not have radiators at first, but when the heat generation increased, radiators were invented.

In the early days, although the CPU manufacturing process looked very backward now, and the main frequency was very low, the power was also relatively low, so the heat generation was naturally not high. Even many CPUs before 486 did not install radiators and were "naked". For example, Intel's 80386 processor had a TDP of 1.85W and a maximum power consumption of only 2.3W, so there was no need to install a radiator. However, it did not mean that manufacturers did not pay attention to the heat generation problem. For example, the CPU used ceramic packaging instead of plastic packaging.

In the 486 period, due to the increase in CPU frequency (although it was still only a few dozen MHz), the heat generation also increased. For example, the maximum power consumption of Intel's 486DX4 processor had reached 5W. At that time, the CPU and motherboard had no safe temperature operation protection mechanism, which caused the CPU to burn out frequently. Therefore, the CPU came with a small passive heat sink when it left the factory, but the heat conduction medium was thermally conductive glue instead of silicone grease, which also meant that it was easy to stick the heat sink on, but difficult to take it off. But there was also a benefit... What is a clip?

By the time of Pentium (or 586), the CPU's main frequency exceeded 100MHz, and the power consumption was greatly increased to 11.2w. Passive heat sinks could no longer meet the demand. Therefore, Intel's first generation of Pentium was equipped with a heat sink with a cooling fan. Although it was small in size, it was very beautiful and had the prototype of an air-cooled heat sink. However, the motherboard did not have a dedicated 3PIN/4PIN pin for the CPU fan at that time, and it needed to be powered from the D-type 4Pin of the hard disk.

However, if you pay attention to the Socket7 CPU slot at this time, you can find that it already has ears on both sides to fix the cooling fan, especially the CPUs with built-in metal covers such as Intel Pentium MMX and AMD's K6-2, which can already use third-party radiators. Of course, later motherboards also have 3Pin sockets dedicated to CPU radiators.

The Socket7 third-party radiator at that time looked like this, which was no different from the ordinary air-cooled radiator now, but the size was much smaller and finally thermal grease could be used.

As CPU performance continued to improve, power consumption continued to increase, so the size of the heat sink also began to increase. However, what's interesting is that in the Pentium 2 era of Slot1, Intel still had some CPUs without cooling fans, but the size of the heat sink, see the picture below.

In the Pentium III and Pentium IV era, the performance, power consumption and heat generation of the CPU increased dramatically, so the size of the radiator became larger and the size of the cooling fan also increased accordingly. However, the bottom area of ​​the 1.xGHz Socket370 heat sink is still the same as the socket. When it comes to the Pentium 4 era of Socket478 after 2.0GHz, this size becomes very large, as shown in the figure below.

However, although the size of the heat sink continues to increase, after the introduction of the 3GHz Prescott core in the later stage of Pentium 4, the power consumption and heat generation of the CPU continue to rise. The simple aluminum fin heat sink can no longer meet the demand, so a pure copper heat sink with better thermal conductivity has also appeared.

However, the pure copper heat sink is relatively expensive and heavy, which adds a lot of burden to the motherboard for the vertical chassis. Moreover, its thermal conductivity is better than pure aluminum, but its heat dissipation performance is worse than pure aluminum. Therefore, copper bottom, copper plug and copper-aluminum combined fin heat sinks have appeared. The figure below is Intel's original copper plug heat sink. Note the red copper core inside.

However, these radiators are completely sufficient for low-frequency CPUs, but they are somewhat incapable of high-frequency CPUs, especially those above 3GHz. Therefore, heat pipe + fin radiators came into being, and they also used copper bottoms to contact the CPU and were combined with heat pipes through reflow soldering. Of course, the price was not cheap at the time, and it was also horizontal (or downward pressure) at the beginning.

Later, people found that standing the radiator up could achieve a reasonable air duct, thereby further improving the heat dissipation performance. Therefore, the tower-type heat pipe fin air-cooled radiator came into being, which is what it looks like now. However, depending on the heat dissipation power, the number of heat pipes and cooling fans is also different, and the size of the cooling fan has also increased to 8cm, 9cm or more. In this way, the tower radiator can handle higher-power CPUs, and the high-end dual-tower air-cooled radiator is not afraid of even the entry-level 240mm water cooling.

Picture

However, air-cooled radiators are inevitably unable to cope with top-level processors such as Core i9, and people are looking for better heat dissipation and lower noise, so water-cooled radiators have also appeared on the market. The entire system of water-cooled radiators can actually be regarded as a miniature version of the northern heating system. After all, the specific heat capacity of liquids is larger, the heat absorption effect is better, and the radiator area is larger, so the heat dissipation effect is naturally better. At the same time, depending on the heat generated by the CPU, water cooling has several specifications of 120mm, 240mm and 360mm. Nowadays, the price of water-cooled radiators is no longer high, and you can even buy an entry-level 240mm water cooling for less than 400 yuan.