Test machine: Windows 7 starter running on an Intel atom (N450, single core) processor. 1 Gb RAM. 160 Gb HDD. A base system restore point was created. Wise 360 was the boot analyzer. Process Hacker provided additional information. Antivirus was installed, tested, uninstalled via Wise Uninstaller, and then system restored for the next program.
I like to have phishing protection and most free antivirus’ do not offer full protection. If an antivirus solution did not have its own built in protection, I ran Mcafee Site Advisor. AVG and Panda each have their own proprietary equivalent protection: So with each of these I ran their software and deleted Site Advisor. (as stated, testing was for personal, not scientific reasons ... hence unusual criteria).
Contenders – in no particular order
Windows Defender (Antispyware – this was my informal base, since it came preinstalled on system)
MSE (Tested 2x: once with real time protection off, second time with it on)
Clam Sentinel (with Clamwin)
Panda Cloud Scanner
Time to Boot System (seconds):
Comodo, Avira, and Digital Defender seem to have a lag relating to their real time protection turning on.
Digital Defender booted in 68 seconds, but it took an additional 26 seconds for its real time protection to turn on.
With Comodo, the system was booted in 76 seconds, but it took an additional +70 seconds for the tray icon to appear. Does this indicate that you don’t have real time protection for that span? It seems to indicate that Comodo is still loading.
Avira was confusing as well. It averaged 63 seconds to boot. But its umbrella, indicating the status of its real time protection, was closed. It took an additional 37.5 seconds for the umbrella to open. This gave a total boot of 99 seconds.
CPU Percentage (%):
Note: There is an element of subjectivity with these CPU readings. As you can imagine, they change every time you look at them. I recorded them when my system was idle and I checked them numerous times per antivirus to try and determine a consistent number. Because of ranges of data, I will present them as raw data.
Defender 30-48.5% erratic
MSE 7-58% erratic this is with real time protection on
MSE 0% protection off
Avast 40-52% (lingers a lot on 47.8)
Clam Sentinel 40% (this is with clamwin)
Amiti Antivirus 44%
AVG 2014 38-45%
Zilla Antivirus 55%
Comodo Antivirus 27-62 (lingers on 44) erratic
Avira 46-50% erratic
Digital Defender 53% erratic
These AVs utilize different scan engines that utilize your resources differently depending on what their scanning. Just because an AV is lightest when idle does not mean it is lightest when working (ex. Opening an office suite or browser). Subjectively speaking, when I took these AVs for a test drive, Amiti Antivirus stood out as feeling the lightest. Clamwin likewise seemed very light but not as refined as Amiti. Immunet was excellent as well, but had occasional small lags when opening heavy programs. I am surprised to relay that MSE was also a light weight contender. I felt some system drag with AVG, Avast, Panda, and Avira: though Avira was worse. Still, despite the slight drag, the system was usable with these.
Number of Processes Running:
This is just in case anyone is interested. I don’t find this info very useful, but it was easy to record. This would include my system processes.
Clam Sentinel 44
Amiti Antivirus 42
AVG 2014 48
Zilla Antivirus 41
Comodo Antivirus 47
Avira 51/47 changes
Digital Defender 48
-Digital Defender did not do a clean uninstall. It left 83 items. Use Revo or Wise uninstaller.
-Moonsecure gave me an application error (exception EA access violation). I disqualified it for this annoyance.
-Clam sentinel is a two part installation. First install clamwin, then install clam sentinel.
-given that MSE is no longer supported for XP, some of these may offer a substitute.
Admittedly, not all of these antivirus solutions are equivalent in protection. Avast, AVG, Panda, and Avira offer capable and reliable protection. But that protection can come with the additional system hit many can’t afford. Weigh the protection you need with the impact your system can handle. If you’re willing to pay, however, I’d recommend Webroot Antivirus. It’s the hand down winner for smallest/lightest antivirus.
Boot winner: clam sentinel, followed by Amiti
Lightest test drive: Amiti
Physical memory % usage: Roboscan, followed by clam sentinel
Big boys of AV run down for boot time (sorry, I don’t consider MSE a big boy anymore, they have tested poorly in all professional AV testing labs):
Panda Cloud Scanner fastest
Again, it should be mentioned that my antiphishing protection skews these results. I wanted equivalent protection and added siteadvisor to those AVs that lacked this capability. Panda uses a proxy which would have no real system impact at boot and gives it an advantage. AVG uses linkscanner, which is potentially heavier than siteadvisor. Avast didn’t have equivalent protection with their site rater, so I used siteadvisor with it instead. Avira was disappointing and has no real excuses.