Just looked into the Event Viewer...
At round 1.08.00 am I have "a request to disable windows desktop manager" followed by "faulty application name cgminer.exe..module amdocl.dll" and to top things off "amdkmdap driver crashed and successfully recovered" 1 sec after that...few hours later fragmentation process starts, finishes and the pc "shuts down ". Have in mind cards fans were working...Anyone