We all know that the performance of CPU is positively correlated with the number of transistors in the chip. It can be imagined that under the premise of the same process, as long as the chip area is doubled, the performance will also be improved accordingly. For example, the packaging of the AMD 3990x processor with 64 cores and 128 threads is really large, which already has half the palm area. Then, if the CPU is big enough, it can achieve almost unlimited performance? < / P > < p > in fact, this is not the case. The current size of CPU is the optimal solution after considering all aspects. If the area of the chip is increased, the performance price ratio will drop sharply, the performance, heat dissipation and power supply will not be balanced, and the data transmission efficiency will be difficult to meet. < / P > < p > first of all, we need to know that CPU chip is a small block cut from a whole wafer. Under the current technical conditions, the wafer can not be perfect, and if there is a defect in the block where a CPU is located, the CPU will become a scrap. < / P > < p > suppose that there are five bad points on a wafer, which are within the range of five CPUs, and the wafer can be cut into 100 CPUs, it is easy to get that the yield of this wafer is 95%. If we double the length and width of the CPU, the wafer can be cut into 25 CPUs, then the yield of the wafer will be reduced to 80% due to five bad points, and the sharp increase in cost is obvious. < / P > < p > If a wafer is only made into a CPU, then the yield will be infinitely close to 0, and it takes countless wafers to make a qualified product. At that time, computers could not even be positioned as luxury goods. They could only be regarded as legendary things. < / P > < p > the heat dissipation of CPU has always been a big problem. With the improvement of CPU performance, the heat generation also increases dramatically. In the face of the current top CPU, the cooling efficiency of 360 water cooling is barely enough. If the core area continues to increase, or even double. Perhaps the 360 × 360 water-cooled array can not meet the cooling requirements. < / P > < p > in terms of power supply, the current motherboard CPU power supply interface is about 3 * 8pin interface, which can meet the 1080W power consumption demand. The total power of our daily computer power supply is only about 5600w, which is very terrible data. With the increase of the number of transistors, the power consumption of CPU will increase sharply. The full load power consumption of thread Ripper 3990x has reached 800W, higher power consumption will bring great pressure to the motherboard and power supply. < / P > < p > although the data transmission between the CPU and the motherboard is completed by pins, the pins will eventually be transferred to the motherboard plane and transmitted around the CPU. Although the area of CPU is doubled and the area where pins can be placed is doubled simultaneously, the perimeter of CPU for data transmission can only be increased by about 0.4 times. If the increase continues, the routing space around CPU will eventually run out, which makes it very difficult to meet the requirements of power supply and data transmission. < / P > < p > it is precisely because of various limitations that the CPU has developed into a standard specification with a package of about 5cm square under the condition of generation by generation update and gradual optimization. And large and small CPU chips are hidden under this package. If we force the chip to be even larger, we can only get half the result with half the effort. It is said that “gta5” will be launched on Google cloud game platform stadia

By ibmwl