Diagnosing a slow running Mac – Part 2: Processor

This short series will discuss some of the common problems that can slow your Mac down dramatically. In this installment we’ll look at processor performance, also known as the CPU.

If you’ve eliminated low RAM as the major reason your Mac is running slow, the next thing to look at is processor power. When people talk about getting a “faster computer”, they are almost invariably talking about getting a quicker processor. However in my experience much of the time this isn’t the problem, unless they are playing games, doing hardcore video editing or computational programming.

So how do you know if your processor is slowing you down? Easy. Open Activity Monitor, click in the “% CPU” column and keep an eye on which Processes are taking more than 50%. If you have a machine with multiple processors you should be seeing programs taking more than 100%. Sounds weird, but each processor core is considered 100%, so if you have a Quad-core machine you have a theoretical 400% to play with. If you click into the CPU tab, you can see a historical activity chart showing processor utilisation per core. If these are consistently high, you machine is CPU performance bound.

The only option in this instance is to get a machine with greater performance. Either a faster processor or more processor cores.