Hi All, I have a problem with running Windows 8.1 under bootcamp where bootcamp itself uses between 25-35% CPU constant. Also when pressing any function keys such as volume or display/keyboard brightness it can take minutes to respond. Then when it does the translucent overlay can stay on screen for a long time before going. This occasionally goes after sometime (like 2 hours) but as soon as a reboot is done it starts again. I have had Windows 7 on this Mac previously which was perfect. I could maybe understand problems if I had done an upgrade but I didn't to try and avoid issues like this. When I moved to Windows 8.1 I did a clean install. I have looked around on this issue but not really found anything that has helped this problem. Anyone else had this issue or have any thoughts on a possible solution? Thanks for your time to anyone who replies.