I purchased avast a few days ago. Up till then my CPU usage hovered between 0-50 with an occasional spike near 100%. After deleting MS Security Essentials and installing avast, my CPU usage is continually pegged at 100% and loading Chrome, web searches and email are painfully slow and sometimes impossible. This has been going on for four days now. Anything I can do?
It sounds like you may have something else going on.
avast! certainly isn’t the cause of any slowdown on my system:
http://www.screencast-o-matic.com/screenshots/u/Lh/1404222789118-48774.png
More information about your system and any other security programs you’re running might help. 