Good real time protection?

i have a "old" computer, running only 512 of memory, and i have avira, avg, and avast, all pro editions, i just wanted to know of any others that were good, or better in your opinion. if im being picky, lol lemme know

Good real time protection?matchless

The best anti-virus is ESET NOD32 then Kaspersky. NOD32 is the only anti-virus that got an Advanced+ rating in tests conducted at http://www.av-comparatives.org/

The most popular free anti-virus programs (AVG and Avast) have poor detection rates (82.82%, 87.46% respectively). Norton is notoriously bloated and takes forever to perform full systems scans.

Good real time protection?norton 2008

Avast would work best with your low memory!
Norton