Incredibly Sluggish PC? How to Easily Detect and Combat High Processor Usage

Does your PC seem to run slowly right after you start it? Did you follow all of the optimization tips we’ve covered on the TuneUp Blog so far? If so, your computer may be bogged down by a renegade process that continuously uses nearly all of your processor (or CPU) resources. In this post, I’ll show you just how much of an effect this has on your PC, what may be the cause and what you can do to prevent this from happening.

What causes high CPU usage?

First of all, high CPU usage is caused by programs that heavily rely on your processor to perform certain tasks. For example, when you’re editing a video or playing a game, your processor usage is usually higher than 50 %. You can check this by right-clicking on your taskbar and selecting “Start Task Manager”.

Make sure that you see the “Processes” tab; then click on “CPU” to sort the list of all of the running programs and processes by their current CPU usage.

In the above screenshot, there is not much going on—the “System Idle Process” is at 99%, which means that the computer is not working on anything at all. However, as soon as I start doing something, such as unpacking a WinRAR archive, a sudden spike occurs until the operation is complete.

This is perfectly normal and considered to be regular CPU Usage. However, if your computer is incredibly slow, and you are not doing anything extraordinary, one of the following issues may be occurring:

1. In many cases, a spyware program, a virus, or a Trojan is causing continuously high usage of your processor.
2. A process that has bugs or just crashed might also be the cause of a high CPU usage. In some cases, a process is caught in a loop; it tries to perform a certain operation, fails, tries again, and fails again. This might endlessly go on and not allow your processor to catch up.

In any case, your processor does not allow you to perform your day-to-day tasks, like sending e-mails, browsing the Internet, and watching a video, in a timely and smooth fashion.

What impact does a high CPU usage have on your machine?

Of course, the TuneUp Blog for Windows doesn’t just talk about optimization issues—we even test them. I wanted to measure the effects of a “busy” CPU on your daily computer routines. What we used—a relatively fast Core 2 Duo with 3 GHz, 4 GBytes of RAM, and a GeForce 9600 GT running Windows 7 64-bit. I also specifically developed TuneUp’s CPU Stressor, a tool to simulate a 99% CPU usage on my machine; you can find it by clicking here or on the following icon to test out my scenarios and see how the high usage affects your machine.

To start the CPU Stressor, which keeps all of the processor cores very busy, double-click on the file, and hit “Start”.

Test: Overall performance with applications

With TuneUp’s CPU Stressor running in the background, I continued my day-to-day routine. Launching Outlook usually takes anywhere between two to four seconds on this machine. With the tool simulating a troublesome process, the startup time clocked in at about eight seconds—at least twice as high!

When TuneUp’s CPU Stressor was enabled, there was a noticeable delay when double-clicking on an e-mail message, especially when clicking “Reply”. Opening Windows Explorer and folders also came with a significant delay, usually between 500 milliseconds and two seconds. It was just unbearable!

Opening a folder full of picture subfolders usually takes less than a second, with the little thumbnail previews instantly shown. In the high CPU usage test, Windows Explorer took nearly ten seconds to display all of the thumbnail previews.

Launching Google Chrome took three seconds, which isn’t bad, but it usually starts in less than a blink of an eye. Closing and re-opening Microsoft’s Internet Explorer browser resulted in it immediately crashing upon restart.

We used WinRAR to compress 550 MBytes worth of data into a single ZIP file; it took my machine 94 seconds with the CPU Stressor enabled, whereas without it, the task only needed 46 seconds.

Performance went down more than 100% in the majority of tests performed. A-100%-CPU usage resulted not only in an absolutely terrible performance but also in noticeable instability.

How can you protect yourself against high CPU usage?

If you suspect that your PC is running slowly, I suggest checking out the Task Manager by right-clicking on your taskbar and selecting “Start Task Manager”. Sort by “CPU” to find out which process is causing the high usage. If you cannot immediately identify the process, type it into a search engine and see what others have to say about it. In most cases, you will immediately find out what program is behind the usage.

First of all, I recommend ending the task immediately in order for your computer to work at its normal performance level. To do so, right-click on the process, and select “End Process”.

Now that you know what the process is, you have three choices:

1. If it’s a program or process you need on a regular basis—and that is taking up a lot of CPU usage—there is only one solution: TuneUp Live Optimization, which is part of TuneUp Utilities.
   This function monitors the CPU usage on your PC and automatically adjusts the performance of the programs that you are actively using. It recognizes if your computer is running at full capacity and temporarily assigns all of the programs that you start and use with a higher priority. You will not even notice that a program is using a lot of the processor’s resources. TuneUp Live Optimization is also very easy to use; you just have to install TuneUp Utilities 2010, and the function will run in the background and prevent your PC from slowing down. I just performed a couple of basic benchmarks, using my CPU Stressor (see above), with Live Optimization enabled and disabled:

   So as you can see, performance is now at its best thanks to Live Optimization. Also navigating around Windows Explorer felt a lot smoother and there was next to no delay when opening folders or clicking on menu items—which is quite astounding, given the high CPU usage.

2. If it’s a form of malware (viruses, Trojan, etc.) that’s wreaking havoc, use an up-to-date antivirus solution to scan your entire disk. We can wholeheartedly recommend Microsoft Security Essentials, as it is very lightweight and efficient. Make sure it’s kept up-to-date, use the “Full Scan”, and delete any malware you find.
3. If it’s a troublesome process that you don’t need, find the corresponding program via Google, and uninstall it.
   If you don’t want to uninstall the program, make sure that it or certain parts of it do not run all of the time. Prevent it from starting up by holding down the “WIN” key on your keyboard and pressing “R”. Type “msconfig” into the box, and hit “OK”. Then, go to “Startup” and see if you can find the process; finally, uncheck it!

The negative effect on your PC’s performance is simply incredible. If a CPU is busy, performance goes down so much that you think you are working on your old Pentium from before 2001. Hopefully, you have learned how to regularly check for these renegade processes and resolve them.

Got thoughts you want to share on this post? We’d love comments!