What is CPU Clock Speed?

ByWaldo Judge 2020-01-03 2002

The main frequency of CPU, that is, the CPU Clock Speed.The so-and-so CPU is usually referred to as the number of megahertz, and this number of megahertz is the main frequency of the CPU. Many people think that the main frequency of CPU is its running speed, but it is not. The main frequency of the CPU represents the oscillation speed of the digital pulse signal in the CPU, which is not directly related to the actual computing power of the CPU. There is a certain relationship between the main frequency and the actual operation speed, but at present there is no definite formula that can quantify the numerical relationship between the two, because the operation speed of CPU depends on all aspects of the performance index of the CPU pipeline (cache, instruction set, the number of bits of CPU, etc.).

Because the main frequency does not directly represent the operation speed, under certain circumstances, the actual operation speed of CPU with higher main frequency is likely to be lower. For example, most of the AthlonXP series CPU of AMD can achieve the CPU performance of Intel's Pentium 4 series CPU with lower main frequency, so the AthlonXP series CPU is named with PR value. Therefore, the dominant frequency is only one aspect of the performance of CPU, and does not represent the overall performance of CPU. The main frequency of

CPU does not represent the speed of CPU, but increasing the main frequency is very important to improve the speed of CPU operation. For example, if a CPU executes an operation instruction in a clock cycle, CPU will be twice as fast when it runs on the 100MHz main frequency as it does when it runs on the 50MHz main frequency. Because the clock cycle of 100MHz is half the clock cycle time of 50MHz, that is, the time required by CPU working at 100MHz main frequency to execute an operation instruction is only half that of 10ns, which is half shorter than that of 20ns working at 50MHz main frequency, and the natural operation speed is also twice as fast.

However, the overall running speed of the computer not only depends on the CPU operation speed, but also related to the operation of other subsystems. only when the main frequency is increased, the running speed of each subsystem and the data transmission speed between the subsystems can be improved, can the overall running speed of the computer be really improved.

The improvement of the main working frequency of CPU is mainly limited by the production process. Because CPU is made on semiconductor silicon wafer, wires are needed to connect the elements on silicon wafer. Under the condition of high frequency, wire is required to be as thin as possible. Only in this way can stray interference such as wire distributed capacitance be reduced to ensure correct CPU calculation. Therefore, the limitation of manufacturing process is one of the biggest obstacles to the development of CPU main frequency.

The main frequency of memory, like the main frequency of CPU, is traditionally used to represent the speed of memory, which represents the highest working frequency that can be achieved by the memory. The main frequency of memory is measured in MHz (megahertz). The higher the main frequency of memory, to some extent, the faster the speed of memory can be achieved. The main frequency of the memory determines the maximum frequency at which the memory can work properly. At present, the mainstream memory frequency is DDR2 memory of 667MHz and 800MHz, and DDR3 memory of 1333MHz. The more high-end ones are calculated by GHz, such as 2.4GHz, which is the main frequency required by high-end enterprises.

When it comes to the main frequency of the processor, it is necessary to mention two concepts closely related to it: frequency doubling and external frequency, which is the reference frequency of CPU, and the unit is also MHz. External frequency is the speed of synchronous operation between CPU and motherboard, and in most computer systems at present, external frequency is also the speed of synchronous operation between memory and motherboard. In this way, it can be understood that the external frequency of CPU is directly connected with memory to achieve synchronous operation between the two; frequency doubling is the multiple of the ratio of main frequency to external frequency. The relationship between main frequency, external frequency and frequency doubling is as follows: main frequency = external frequency doubling. In the early days of CPU, there was no concept of frequency doubling, when the speed of the main frequency was the same as that of the system bus.

With the development of technology, the speed of CPU is getting faster and faster, memory, hard disk and other accessories gradually can not keep up with the speed of CPU, and the emergence of frequency doubling solves this problem, it can make memory and other components still work at a relatively low system bus frequency, and the main frequency of CPU can be infinitely improved by frequency doubling (in theory).

We can regard the external frequency as a production line in the machine, and the frequency doubling is the number of the production line. The production speed of a machine (main frequency) is naturally the speed of the production line (external frequency) multiplied by the number of production lines (frequency doubling). Now the manufacturers have basically locked the frequency doubling, to overclock only from the external frequency to start, through the frequency doubling and external frequency collocation to the motherboard jumper or set soft overclocking in the BIOS, so as to achieve part of the overall performance of the computer. Therefore, when buying, we should try to pay attention to the external frequency of CPU. What is the main frequency of


 You may also want to read:
 Does the HUAWEI FreeBuds 3 Work Well With iPhone?
 Realme Buds Air VS JBL C100TWS: Which is More Worth Buying?
 Does the i12 TWS Earbuds Work with Android Phone?
 How to Charge your AirPods Pro and Check the AirPods Pro Battery State?

Gearbest Daily deals up to 69 percent off

Extensive Product Selection

● Over 300,000 products

● 20 different categories

● 15 local warehosues

● Multiple top brands

Convenient Payment

● Global payment options: Visa, MasterCard, American Express

● PayPal, Western Union and bank transfer are accepted

● Boleto Bancario via Ebanx (for Brazil)

Prompt Shipping

● Unregistered air mail

● Registered air mail

● Priority line

● Expedited shipping

Dedicated After-sales Service

● 45 day money back guarantee

● 365 day free repair warranty

● 7 day Dead on Arrival guarantee (DOA)

You might also like

HOT TOPICS

Related Products