Computer hardware: Chip tip

Q. I am looking to purchase a new computer, and I notice that many of them come with multiple core processor chips. This has me wondering how many core processor chips I really need in my desktop computer.

A. In my opinion, you should purchase a computer with at least four, but no more than eight, processor chips. I’ll explain why, but first here’s a quick history lesson. The older Windows XP (standard edition) operating system supported only one core processor chip (not to be confused with the other various computer chips contained in the computer related to the video card, motherboard, hard drives, etc.). This meant that a Windows XP computer could perform only one task at a time, but to coordinate multiple activities, Windows XP employed a time-slice mechanism in which the core processor spent 1/50th of a second on each process to make it appear as if it were performing multiple processes at the same time. For example, the core processor might spend 1/50th of a second reading your hard drive, the next 1/50th of a second recalculating your spreadsheet, the next 1/50th of a second displaying the results on your screen, and the next 1/50th of a second writing to a USB drive. The processor would then repeat those four processes in 1/50th-of-a-second intervals until each task was completed. In this manner it appeared that your Windows XP computer’s core processor was performing these four functions simultaneously, when technically it was not.

Today, making computers actually perform separate tasks/processes at the same time requires multiple core processors, which is why computer manufacturers have moved to multiple core processor designs. Based on this explanation thus far, you might conclude that more processors translates to faster performance, but this is not necessarily the case because at some point adding core processors has diminishing returns. This is because while your computer may frequently be doing four or five things at a time, it is rarely doing nine or 10 things at a time, so adding a ninth or 10th core processor is almost pointless. For example, in addition to the four processes mentioned above, assume your computer is also displaying your webcam, scanning an image, retrieving a webpage, and playing music. Even in this unlikely scenario where eight activities are being processed, eight core processor chips are sufficient to handle the workload simultaneously.

The various editions of Windows 8.1, 8, 7, and Vista are designed to support a maximum of 32 or 256 core processor chips, depending on the specific version (Home or Professional) and the operating system’s architecture (32 or 64 bit). However, if you purchase more than eight core processor chips, those additional chips will likely sit idle the vast majority of the time, simply because your computer rarely performs that many operations at the same time.

Important caveat: I should note that there are slight exceptions to the above-stated reasoning. For example, my 2-year-old HP Envy desktop computer ($850 from Sam’s Club) has eight core processor chips, and my 64-bit Excel application has the capacity to use all eight chips at the same time to tackle voluminous calculations. Therefore, if Excel needs to make a voluminous calculation, it can distribute that calculation across all available core processors, as suggested in the Excel options setting dialog box below.

To extend this example further, if my computer had 256 core processor chips and I frequently performed voluminous calculations, Excel could simultaneously use all 256 cores to perform the massive calculations faster. Therefore, in special situations, more than eight cores may be warranted.

About the author

J. Carlton Collins (carlton@asaresearch.com) is a technology consultant, a CPE instructor, and a JofA contributing editor.

Note: Instructions for Microsoft Office in “Technology Q&A” refer to the 2013, 2010, and 2007 versions, unless otherwise specified.

Submit a question

Do you have technology questions for this column? Or, after reading an answer, do you have a better solution? Send them to jofatech@aicpa.org. We regret being unable to individually answer all submitted questions.