On occasion, my AVG has a pop up that alerts me to Firefox using too much of my computers resources. I usually have several tabs open. When I check it with my task manager it shows several hundred megabytes being consumed by Firefox. (250 mgbts) It may be Kbs. Right now I am pulling 150,00 K with only 1 tab open and no problem. AVG suggests I close Firefox and re-start it. So far I just ignore it. I check for viruses,etc. and nothing shows up.