Look at your system settings for anything positive, if you connect to the internet, delete any internet pages and cookies from your system, look to turn everything off you can, wireless conection device etc .(I don't have any virus programes on my studio pc it's kept to essential stuff only to stop any scheduled tasks from kicking in.) Simple screen background no screen savers.
And finally, defragment your computer at least once a month, (they say, but I say every 3 months or so, or when you've moved stuff around and removed unwanted or demo VST's). I looked at mine this afternoon, and was amazed to see 40% of my drive needed attention.
Just a thought...
