I was upgrading my hard drive to a SSD. When trying to do a clean install of Win7 I could not get past the first screen. I had no mouse or keyboard. I did not leave the old hard drive plugged in. Long story short I gave up on the install and plugged in my old hard drive. Even though i completely shutdown the computer it seems that the windows install files were still in memory. When I turned the computer back on it was making changes to the registry and other settings. After a very long time it eventually booted to the desktop and everything seems ok but why was it making changes to my original installation and is there any way to remove the install files from the memory? Shutting down and unplugging the computer doesn't seem do it.