Not so good experience with Dell E6540 when it comes to gaming.
It has 8790M graphics but cooling solution not enough when it comes to gaming.
It starts fine and gives good fps even on heavy games but after 10 minutes cpu/gpu start throttling down and game starts stuttering.
I have Dell XPS L702X which also have only one fan for cpu and gpu but that thing pushes out heat like crazy and keeps going full speed no matter what.