Greeting,, I have many issues using windows 8.1 in boot camp. 1- After PC sleep or laying the lid down, it will completely freeze after couple of minutes and won't function unless restart by holding power button. Disabling hibernation did not fix the problem. 2- Sometimes it will lag and pressing mute or rising volume will function after minutes and hanging, this also need to be restarted to happen. 3- Also sometimes after starting, it get load cpu usage and the fan kicks high for around 3 minutes, task manager shows boot camp and some other applications utilising more than 55% of cpu usage, windows host up to 35-40%! 4- I have run some test, from what i see in Event Viewer in Windows it shows Kernal-Power errors related to cpu, and many warnings and errors also. I've run Intel Processor Diagnostic Tool in windows, middle of the test the screen kept rotating ( don't know if it some testing method) even after the test complete the screen still rotating and showing strange lines and colors, i merely see to click on restart and then it back to normal after restart. Also i've run Memtest for about 8 hours, no problem Apple test also shows no problem (Holding D after restart) most of the problems is under windows only, OS X seems to run just fine. Any other members have same problems? or know to how fix such things? i want to run CPU test in OS X because i think i have a problem there, could any one suggest a method for OS X? Thank you.