Clock Speed - Benchmark for Processors?

Intel i7 - Base Frequency 2.80 GHz, 4.70 GHz (Turbo Frequency)

Intel i9 - Base Frequency 2.2 GHz, 5.8 GHz (Turbo Frequency) 

AMD Ryzen 7 - Base Frequency 3.4 GHz, 4.6 GHz (Max Boost Clock)

Whenever we shop for a laptop or home PC, we note the processor speed. The saying being more the clock speed, higher the performance. However, efficiency of a chip is determined by a range of other factors

What is clock speed?

The CPU (Central Processing Unit), or processor performs various arithmetic operations, at any given time. This is performed by opening and closing billions of transistors, embedded within it. That constitutes a cycle. 

Simply put, clock speed is the number of cycles executed per second, calculated in GHz. 

So, a processor having 3 GHz speed, performs 3 billion cycles per second. Higher this ratio, better the performance. At least, in paper.

But there are other things in play, when looking at the overall functionality.

 

Multi Core processing

A single chip contains multiple processors (core), each acting independently. They execute two or more tasks simultaneously, within a single clock cycle. This boosts efficiency and speed.  

There is quad core (4 core), octa core (8 core) or even 32 core (AMD Ryzen Thread ripper 3970x) processors. Higher the core count, better the multitasking

Multi-Thread

Taken from the pages of multi core, here a single program is split into separate threads. They are then executed in parallel, by different cores. It would seem like multiple instances of the same program, running in a loop. Each thread has its own id and provision to prevent errors, like race condition. This occurs when two threads access the same resources simultaneously.

CPU Cache

This is a memory storage, excluding the main memory (RAM). It stores frequently used instructions and data, for faster access. Sometimes within the processor, they can also be placed in a separate chip, connected via a BUS. 

Highly expensive, they cannot be upgraded beyond a certain limit.

Last but not the least, there is a special technique, known as Overclocking. This is usually referred to as Turbo Boost (Intel). Here, the processor runs at a higher clock speed, than its base configuration. This is done after carefully calculating the core temperature and availability.  

Initiated by the processor itself, no special command, or instruction is needed from the user. 

 Additional Information:

https://www.geeksforgeeks.org/clock-speed/

https://www.javatpoint.com/what-is-a-multicore-processor