Every once in awhile I will here my cpu fan speed up and I go into task manager and find a setup.exe process running. I kill the process and the fan slow down. I do not get anything coming up on the desktop like it would be installing anything. I have run MS Security Essentials, Malwarebytes, and Kasper sky Online Scanner and no problems found. How can I find out what is going on. Computer runs okay, does not slow down when setup.exe is trying to run. Any ideas what I can do to find out what is going on?? XP Pro 32bit with 4GB of ram.