Avast uses too much resources to compare to Dr.Web, Nod32, AVG 6 & 7(That just came out), and it even uses more than Kaspersky too. Now Norton(second biggest), McAfee(the biggest hogger), PC-Cillin, and a few others no need to mention are way out of the line for us slow pc users. I know Norton has its power but it has its weakness, McAfee not a fan, etc. Just cuz they use a lot of resource dont mean they powerful.