Windows 7: The most lightweight antivirus?

Could anyone please tell me which one is considered the most lightweight (uses the least RAM/proc) with real time scanning (or resident shield in AVG) feature only?

No need to consider the capability, features (firewall, antimalware etc).

Microsoft Security Essentials

Raymond.CC Antivirus Performance Benchmark Test

An antivirus considered lightweight on one computer won't necessarily be considered lightweight on another.

Here is mine, I am not really in a position to pass comment on other AV's as it has been so long since i have used any other.

If this is for the machine listed in your system specs then the amount of processes and RAM is not going to to cause system slowdown. There are more important factors such as CPU usage, I/O Reads and I/O Writes.

ESET NOD32 has often been considered very light over the years and it uses 40-50MB. Some find Microsoft Security Essentials heavy but most don't. It uses 50-60MB or sometimes more.

Avast! and Norton are two of ones that use the least amount of RAM. I don't notice either of them on my low specced machine. The last time I used Avast! it tended to use a few MB more when surfing with Firefox but on average they use about the same. Norton currently running:

The best advice is to try and see what you like best. I have run into instances where software appeared to be using very little resources but would affect the time that it took for a browser, email client, or software to open and run. It is all about personal preference. I have heard very good things about MSE and run Avast personally.

Unfortunately MSE is one of the AV programs that uses the most RAM. About 50MBs versus 8MBs for NIS.

you can remove the virus yourself, thats as lights as it gets

hmmmm.....the quest to find the lightest av is an endeavor in vain....for it takes more than just ram usage...to label an av as light...it depends on your OS/other security apps/Disk I/O/no.of processes....an av with a web guard might slow your browsing speed...but its a trade off for better security....some claim to just scan on execution other realtime that would affect your systems response....but which is safer ? that's debatable...so try and settle for one that you and your system likes...

MSE's installer is lightweight but I cannot say that it's light on system resources. On my PC, it eats up like 50-70mb. You might want to consider other AV's out there which consumes less RAM and are more effective than MSE.