It’s no surprise that malware can impact your computer’s speed. It’s one of the conclusions people often jump to when their computer slows down, and it’s not uncommon for them to be quite right.
Interestingly enough, malware can impact speed before it arrives, while it’s present, and even after it’s been removed.
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Running too much (or poor-quality) security software commonly impacts performance without any malware being present. Of course, malware on your machine can slow it down, as can its leftovers after having been removed. The best approach it to stay safe and avoid malware in the first place.
Malware’s impact before it arrives
One of the most common causes of computer slow-downs is trying to run too much software.
One common cause of running too much software? Fear of malware. Or, rather, installing too much (or poor quality) security software on your machine to avoid it.
Having too many different security solutions installed is a fast path to problems, and one of those problems is speed (or the lack thereof). The various security software packages come into conflict or duplicate efforts to the point where your computer is spending so much time scanning and trying to stay safe that it can do little else.
Pick a solution and stick with it. I have recommendations, but regardless of what you choose, make sure it has a good reputation and meets your specific needs.
Don’t randomly add more tools. If you want to replace the solution you’ve chosen, uninstall it before installing its replacement to avoid conflicts1.
And of course, ignore the advertisements claiming amazing results or one tool that does it all. There are good solutions out there, but the poor ones are advertised right alongside them. Do your research.
Malware at work
Malware on your machine can absolutely slow it down. It can do a lot more, of course, but when it’s running correctly (by the malware author’s definition of “correct”), malware’s initial (and sometimes only) symptom can be a machine that has begun to slow down. Ransomware gets the most press these days; it systematically encrypts files, taking computer resources to do so.
This is also very much related to the issue of too much software: malware is additional software running in the background on your machine. It’s not always designed to behave nicely, and as a result, it can have a negative impact on performance.
There’s no magic bullet here. The solution is to avoid malware in the first place and remove it when you encounter it.
The impact of malware removal
Even after successful malware removal, its memory can linger in the form of poor performance.
The problem is, not all security software does a good job of both removing the malware and returning your system to the state it was in before the malware showed up.
In fact, even with the best anti-malware tools, there may not be a way to return to a pre-infected state. The now-departed malware could have affected other things, like system settings or other applications, such that the net result is a slower system even with the malware no longer present.
When that happens, the only pragmatic recourse is to either revert to a backup image taken prior to the malware’s arrival, or reinstall Windows so it can reset everything back to a known good state.
Of course, the best solution, as always, is not to allow malware on your machine to begin with.
Staying safe
Keeping your machine safe is something we hear often. I call it the “litany of safety”.
- Make sure your computer is behind a firewall; your home router will likely do.
- Run good, up-to-date security software; Windows 10’s Windows Security may be enough for most.
- Make sure your security tools are configured to keep themselves up to date.
- Keep all your computer’s software, especially Windows itself, up to date.
- Be skeptical. Learn to identify scams, phishing attempts, and suspicious email attachments.
- Secure your router.
Staying safe from malware and recovering from malware infections is a huge topic, but those are the basics. You can read more about them here, in what I consider my single most important article: Internet Safety: 7 Steps to Keeping Your Computer Safe on the Internet.
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Footnotes & References
1: Except for Windows Security (aka Windows Defender) — it will simply step aside if you install a different solution.
I read your article “Another Reason Your Computer Might Be Slow” I agree with most all of it. I have used The 3 A’s for years I prefer the pay versions and like the Free Avast the best. I have compared the free and pay versions of CCleaner, Malwarebytes and SUPERAntiSpyware. I like the free versions. I have found that SUPERAntiSpyware does a far better job of finding and removing spyware than either of the other two. CCleaner is the quickest way to clean out all the temp files including temporary internet files. Malwarebytes is good for more dangerous malware that you almost never see. Since the newest builds of Windows 10 have come out professionals I know have said you don’t need any of those anymore because Win 10 security is that good. Well if it’s that good why do I find my system slowing down (I am running an i7-3770 w/16gb ram) and when I run the three, Malwarebytes, SUPERAntiSpyware, and CCleaner in that order, Malwarebytes finds almost nothing, SUPERAntiSpyware finds upwards of 300-400 legitimate spyware and sometimes a Trojan or two and the newest CCleaner finds an additional 20-30 trackers plus cleans out the TEMPS. My preference is Free CCleaner and SUPERAntiSpyware. I keep the Windows 10 Security on and running and I run CCleaner when we (my wife uses PCs to surf) are done for the day just before I turn the Computer off. About every 3 to 4 days I run SUPERAntiSpyware. I almost never need to run Malwarebytes. I have used this regime for 15 years and it works fine for me.
I recently have become interested in the PC Matic. It would be nice to not need to run anything. I have two desktops and two laptops. We don’t use the laptops very often but it would still save time. Could you tell more about how it would replace what I use?
to the guy with 3 malware removers. 3 is too many and if u use a free malware app, they do a good job of preventing malware but they do not remove them if u already have them. However, use task manager and see just how much resources 3 of those apps use. you will be surprised by how muse ram is being eaten up. 16 gig os satisfactory but if you have lots of apps running then make a wise decision and remove two of them. Windows Defender rocks. For task manager hit contr.-alt-delete at the same time or type task manager in the search bar.
It depends on how you have those malware programs configured. You can have a few installed without any impact on your computer as long as you only have one working in real-time scanning mode. If you have more than one in real-time mode, your computer will suffere more than using resources, the different antimalware programs can conflict and cause real problems.
You can use the others for periodic virus scans. And most free antimalware programs do remove malware they find as slong as they can.