The CPU doesn’t really get any hotter than other competing notebooks, but the GPU does. For a machine with three heatsinks and three shared heat pipes to allow a GTX 960M to reach above 70C on a mild game like Diablo 3 is disappointing. For comparisons’ sake, a Clevo P650SE with a GTX 970M (a much more powerful GPU) keeps its GPU at 65C or below in the same game.
When running the Unigine Valley benchmark, the GPU hit 76C. A Clevo W230SD, running the same GPU, hit 68C in that same test. To put that into perspective, the W230SD is a 13.3” machine with a single heatsink/fan to cool both the GPU and CPU. In fact, in most games tested (including demanding titles such as Crysis 3 and Dragon Age Inquisition), the W230SD kept its 960M cooler than the Inspiron 7559 does running the comparatively simple Diablo 3.
Additionally, the keyboard temps under load got much toastier. I recorded a high of 46C in the top-centre of the keyboard (around the number 8-9 keys), and that was very uncomfortable to touch. However, the area around the WASD keys stayed under 35C, so for most games, it isn’t too bad at all.
The noise under load is loud, but if you’re using a headset it won’t bother you. It isn’t a high-pitched whining noise, just the sound of fans pushing air.
Oh, all these temperatures were AFTER I used XTU to undervolt the CPU by around -50mV.
Overall, while the temperature/noise levels aren’t horrible, they’re worse than I expected given the cooling solution Dell put in, and given how smaller notebooks with similar specs and less fans/heatsinks do a better job.
All temperature readings are in degrees Celcius at an ambient temp of around 22C.
Excerpt from
http://forum.notebookreview.com/threads/inspiron-7000-15-7559-quick-review.783284/