Everyone wants an efficient computer, whether for playing games or performing other tasks. And since modern operating systems can multitask, it seems to make sense to get processors with more cores, or does it? Would adding more cores to a processor yield significant improvement compared to the cost involved? To help you determine whether multi-core processors are necessary for your system or not, this article will show you what you need to understand to arrive at an informed decision.

Multi-Core Processor

First, what exactly is a multi-core processor? Any computer processor that has two or more CPUs (or cores) is known as a multi-core processor. Each of the CPUs or cores executes instructions as if the system runs on many processors even though it is just one processor chip.

A single-core processor is significantly slower than a multi-core processor because it takes longer for a single-core processor to communicate with other parts of the computer. Multi-core processors can run several processes or programs at the same time. This means better performance when you run programs with heavy demands on the CPU or when you are multitasking.

Multi-core processors were manufactured to solve the problem of clock speed that single-core processors encounter when they hit their physical limitations. Adding extra cores on a single chip means that a CPU can handle more data effectively.

Initially, manufacturers produced only two cores in a single CPU. It is no longer news that you can now get a processor chip with ten or more cores! This is particularly useful for effectively running programs with complex processes and calculations.

Process and Thread

Two important concepts to consider are processes and threads.

Processes are tasks, such as applications that run on computers. A process is made up of one or more threads.

A thread refers to a stream of data from a program that passes through a processor. Every program running on a computer generates single or multiple threads. Multiple threads can exist within a process and share resources while executing independently. This is known as multithreading.

With multi-cores, systems can effectively execute more than one thread at the same time. This means that each core in the multi-core handles a separate stream of data, thereby increasing performance and allowing several programs to run simultaneously.

This technology was originally developed with servers in mind because servers usually run multiple programs concurrently. In the past, the technology appealed to the enterprise customer, but with multitasking and the complex nature of personal computers in recent times, more cores are now built into PCs.

But here’s the thing; each process that runs on a computer has a primary thread that occupies just one core. In other words, a large chunk of a program’s speed is determined by the core which the primary thread occupies. Other secondary threads from the program are delegated to different cores. This means that doubling cores doesn’t necessarily increase the speed or performance of the program.

However, more cores mean that while the primary thread uses one of the cores, other tasks can be handled by the rest of the cores at the same time. Therefore, massive programs (such as a video-encoding application) will run better on a system with eight cores, for example, than one with four cores.

Here’s another angle that highlights the advantage of multiple cores over single-core processors. During multitasking, a single-core processor must switch quickly between threads to manage different processes because it can’t handle more than one thread at a time. Conversely, a multiple-core processor can manage several threads concurrently because the data is split between each core. This makes data transfer to happen a lot quicker.

Clock Speed

Clock speed refers to the rate at which a processor performs or executes a task. Clock speed is measured in gigahertz (GHz). To illustrate, imagine a car with a powerful engine. The more powerful an engine is, the faster the car runs. This applies to a computer too. Consider the CPU as the computer’s engine – the higher the CPU’s clock speed, the faster the computer will perform. Your computer’s CPU is continuously completing calculations to allow your apps to run efficiently.

Generally, if you have a processor with higher clock speed, your computer will complete its calculations at a faster rate, and your programs will run faster and better. For example, a 2.5GHz processor has 2.5 billion opportunities per second to complete a task, while a 3.0GHz processor has 3 billion chances (or can be about 20% quicker).

It is challenging to compare processors clock speeds across different brands. For example, it is unreasonable to compare the speed of a Pentium 4 CPU to an Intel Core i4.

However, clock speed doesn’t necessarily tell precisely how long a processor will take to accomplish a task. As an example, a person who drives slowly but arrives at their destination without getting lost is faster than a person who drives quickly but always gets lost. So, if a 2.5GHz processor can complete a task in 2 clock ticks but it takes five clock ticks for a 3.5GHz processor to achieve the same job, the so-called slower processor is quicker in this case.

Do You Need More Cores or a Higher Clock Speed?

Multi-core offers high-performance computing just as higher clock speed significantly increases processing rate. The question is, should you go for a processor with fewer cores and more top clock speed or a processor with more cores and lower clock speed? To answer that, let’s take a quick look at the pros and cons of both options.

• Fewer cores with higher clock speed: A processor with fewer cores and higher clock speed means higher performance at single threads. The processor is also likely to cost less. The drawback, however, is that it has fewer cores between which to split apps. Also, it has a relatively weaker performance with multi-threads.

• More cores with lower clock speed: Apart from offering support for multi-thread applications, a chip with more cores and lower clock speed is usually a cost-effective way of improving your computer’s performance. This means there’ll be hardly any issue of reduced performance even when you run many applications at the same time. It is also a great option if you want to run multiple virtual machines. On the downside, its single-thread performance is relatively lower than a processor with higher clock speed.

Here’s an example that can help you understand this better. Let’s compare the speed of the individual cores in two separate CPUs of the same brand. One of the CPUs is a dual-core processor with 3.5GHz clock speed, and the other is a quad-core processor with 3.0GHz clock speed.

When you consider the cores individually, the dual-core processor is roughly 14% faster than the quad-core processor. So, it is more efficient to run a single-threaded program on the dual-core processor. On the other hand, a multithreaded program or a program that uses all four processors will run about 70% faster on the quad-core processor than it would on a dual-core processor and, thus, is more efficient in such case.

Now, to answer the earlier question, if possible, and if your computing task requires it, go for a CPU with the highest clock speed and, at the same time, offer as many cores as possible. But because this option is usually more expensive, you may have to strike a balance between clock speed and the number of cores bearing in mind the pros and cons listed above.

An excellent way to arrive at a better decision is to find out whether your most-used applications support multithreading. Doing this will help you to decide whether to go for a processor with the highest number of cores and slower clock speed (for example, a 6-core chip at 3.2GHz) or a processor with fewer cores and higher clock speed (for example, a quad-core chip at 3.6GHz).

Although modern operating systems all have multithreading capabilities, individual applications need to support multithreading before any significant performance improvement can be noticed.

In other words, the overall efficiency of a computer that runs on multiple processors will not make any meaningful performance impact without software that supports multithreading. If an app will only run on just one core in a 10-core processor, it would be better, cheaper, and maybe even faster to run it on a dual-core processor that has a higher clock speed.

In Closing

You’ll probably not see any significant improvement or benefit of having more than two or four processor cores if you are a primary computer user. For the majority of computer users, a dual-core processor or, at most, a quad-core processor is more than sufficient. As an example, if you primarily use your computer for simple tasks such as surfing the web or checking your emails, you will not notice any significant benefit of adding more processor cores.

On the other hand, if your work involves complex tasks such as complicated math or science programs, high-end gaming, CAD or graphic rendering software, video editing, and the likes, then a high-core-count processor is best for you. You don’t have to be “modest” core-wise if you use your computer to perform demanding or heavy tasks. A computer with an 8-core or 10-core processor will serve you better than one with a dual-core processor.

So, before thinking of getting a multi-core processor, you should first determine if your task requires a high-core-count. It would be redundant to get a multi-core processor that serves no purpose besides bragging rights. It is now standard practice for many business computers to come with dual-core or quad-core processors. These processors are more than enough for many basic computer tasks.