I've tried many av products..and from my experience best antivirus scanners has to be PC Cillin 2002 and Kaspersky Personal Pro ver.4 or late. They have too many features unlikely 'everywhere sponsored' Norton AV's. Faster and efective than NAV in all comparative tests etc. I'm workin on win XP , Cel.667mhz, 320MB Ram,20GB hdd,GeForce 2mx 400 64MB,and so far no problems at all with