On Saturday, February 13, 2016 at 12:55:39 PM UTC-5, wrote:
I stumbled on this topic while searching something else, but am posting because I have a Precision M6500 that did this a lot. I applied the fix found in the "verified answer" he http://en.community.dell.com/support...519/t/19323478

The common problem is due to the video card getting a false overheating signal. My screen was blanking a few times a week, but it hasn't happened once in the year and a few months since applying the fix.