I had the first pop-up on my computer in a very long time the other day so I decided to do some cleaning. Using AVG free, MalwareBytes and Spybot S&D at least twice each, I turned up nothing. Finally AVG picked up an infected Netbt.sys. Other than the pop-ups I also get random FPS drops in videos and games at random times. This requires a restart to fix. After looking around for solutions i ended here with questions... It's been awhile since I've done any real cleaning. Should I just reformat? If I choose not to reformat, should I replace the file? I don't have a 'clean copy' of my own. I'm running Win7 32bit as a (legal) download. I can post logs from the above programs, but they always return clean other than AVG occasionally picking up the netbt.sys and doing nothing about it.