said by Shootist:
Not sure it is Chrome. Could be something else on your system.
This shows both in Windows Task Manager as well as Chrome's internal task manager where it reports about a 20% or so CPU usage with nothing going on.
Chrome's internal task manager shows only Chrome and it was showing 20% CPU for the Browser process. The below picture is Chrome's internal task manager and on this machine shows the Browser task using 2% vs the 20% I'd see on the other machine.