I've managed to solve this problem.....nothing wrong with hardware! Its your Windows 7 Aero...ie. analogue clock, picture gallery....all these items will not compromise with AutoCAD 2012. I have changed my desktop to normal (still) and ever since I've had no problems for months!
Goodluck to you all!!
I've had this problem just today and I can say both solutions seem to work for me. I strongly dislike the ribbon as the classic view worked just fine, you know where everything is etc. But a lot of programmes are going this way (probably to make you feel like you get something new for your money).
Anyhow the aero solution worked too so I am going to stick to that for the time being and labour on with the ribbon.
So thanks to all who sussed this one out. Thanks heavens for this forum.
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