BleepingComputer.com Basic Concepts: Processory Speed Versus Memory: Which is more important?

Introduction

A very common question I am asked is which is more important, the speed of the processor or the amount memory. This is a difficult question to answer and it would help if we had some understanding of what each component does and how they relate to each other. This article will strive to teach you the fundamental tasks of both memory and the cpu and how they relate to each other. Hopefully at the end of this article, you will be able to answer this question yourself.

Central Processing Unit (CPU)

The CPU is the brain of the computer. It's job is to take information from the various input devices, the operating system, and software and execute the instructions that it has been given. A CPU executes a certain amount of instructions within a grouping called a cycle. The speed of the CPU is measured in how many cycles it can perform in a given second. A speed of one cycle per second is called a hertz. Therefore a CPU that has a frequency of 1 million cycles per second has the speed of a Megahertz, and a CPU that has a frequency of 1 billion cycles per second is a Gigahertz. This is illustrated in the table below:

Therefore to have a very high CPU Speed is a good thing, because more instructions per second get executed. On the other hand, with current speeds where they are, most computers coming default with at least 2 Ghz, you will start to see a diminishing return on the visible speed differences between one processor and the next speed. Computers of at 2Ghz should be more than fine these days for most applications and you will probably not see much of a difference by increasing the speed of your processor when using standard applications. Games on the other hand can be more CPU intensive, and if you are going to be using your computer predominantly as a gaming machine, then it could not hurt to spend a few extra dollars on the CPU. You must remember though, to save some money for your memory, as that is just as important to having a fast machine.

Computer Memory

Just as important to the speed of the CPU is the amount of memory you have in your computer. Memory is the temporary storage place for your computers information. When a computer is manipulating some sort of information it is placed in the memory to be retrieves or manipulated later. If all your usable memory gets filled up, the computer will then start storing temporary data on to your hard drive in something called a swap file. When the CPU is ready to use that information it will then read it back from your hard drive and place it into memory where it can be used.

As you can see when you use a swap file, and the CPU needs to access the data it becomes a two-step process in retrieving that data from the hard drive and then stored in the memory, instead of a one step process of reading the data directly from memory. Even more important is that reading data from memory is many many times faster than reading that same data off the hard drive. With this in mind, you can see how it is important to have as much memory as you can, so that the swap file on your hard drive is never used, and all data is stored and read directly from your memory.

Conclusion

With all this information we are still left with the burning question of "Which is more important, Memory or CPU Speed" and the answer is neither and both. Got you there didn't I? The real answer depends on how much you have to spend on your new computer and what the base system is. If the base system is at least 2 Ghz then I would apply the money towards memory, otherwise I would increase it to over 2 Ghz. If you have money left over I would spend your up to your budget to increase your memory to 1 GB or as close as you can get. These days, you really should have at least 512MB of memory.

I hope you found this article to be informative and helpful. If you have any questions, suggestions, or comments please feel free to discuss them in the forums.