Why Does McAfee Slow Down a Computer?

By James Wright

McAfee's operations can slow your entire computer down, hindering your work.
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McAfee's antivirus software comes with plenty of functions and features, but this plethora of options can cause problems on some computers, especially older ones. McAfee offers the ability to scan your computer and update automatically, but these operations take up RAM and bandwidth, giving you less power to work with. McAfee can also slow your computer if it isn't built to handle it; if you have an older machine, it might not meet its system requirements.

Automatic Scans

McAfee scans your computer automatically, which saves you having to keep on top of it yourself. By default, McAfee scans once a week, but it doesn't politely wait until later if it sees you're busy; it starts scanning on schedule every week, even if you're working. Scans use a lot of your RAM and processor power, which can drastically slow down anything you're trying to do. To alleviate this issue, set the automatic scans for a time when you're asleep or away, or disable it completely (but don't forget to scan your computer occasionally).

Automatic Updates

McAfee maintains a database of virus definitions to keep itself up to date with the latest viruses and other threats. To do this, it uses your Internet connection to download these definitions. This is also an automatic feature, and while it doesn't use quite as much processor power, it will take up your bandwidth while it downloads the definitions. You may also notice some slowdowns as it installs the updates. The solution here is the same as before. However, if you opt to disable the updates, do them yourself with more frequency than scans, because definition updates happen regularly.

Full System Scans

Antivirus programs will often suggest running full system scans overnight or while you're away. Full scans use up so much processor power that it's an incredible hassle to try to do anything else at the same time, because McAfee needs to look at all your files and scan them for any issues. However, you can improve the speed of scans themselves by defragmenting your hard drive. When the files aren't fragmented, they're easier to scan and complete.

Inadequate Hardware

Older computers will struggle more with McAfee and antivirus software in general. McAfee asks you to have at least 512MB RAM for Windows XP and 2GB of RAM for Windows Vista and 7, as well as 500MB of free space and a 1GHz processor. For some systems this is not an issue, but for computers that barely meet the specs, simply having McAfee installed will slow your computer down even when it's not scanning or updating. If you have the funds and know-how to improve your system, upgrading your RAM is one of the easier methods of fixing this problem.