Thanks zigzag3143 for your valuable suggestion. I will remove kingsoft pc doctor and online armour first if i still face BSOD then i will remove avast. I have also posted the minidump in the avast forum where a avast team member noticed that and hopefully they will do something about it. I will monitor the behaviour of the pc for a few days and i will report back if i run into more problem. Thanks for your time and suggestion.