It's not AVG, but does "Mamutu" have real-time protection? You should check if your firewall allows the game to be played, but I really don't think that that would cause locking up. Try to download new drivers for your video card.I have a Intel PentiumD 3.73ee, Asus 8500GT, and 2 gigs of Corsair memory. When I play the firewall (Zonealarm), the antivirus (AVG), and antispyware (Mamutu) thats all.