my system is very unstable now. i m now using kaspersky virus removel tool.my system's graphics driver always being creating problems. my system cannot boot always sometime it can not enter after the windows boot screen is apeared .i m using win xp (32 bit) sp3.plz help me.also my system becomes very slow. i have formated my system several time (c drive)but the problem is there.i m now using kapersky internet sequrity demo vertion.it shows there is no virus