Wile the P35x v3 may not cool components as well as the G751jy (the asus is over twice as thick) The palm rest is actually cooler than normal body temperature so it wont feel warm, the same cannot be said for the keyboard as it gets kinda toasty especially with that i7 and the 980m in that slim package. But it works, and works well enough. With arctic silver thermal compound and undervolting the cpu, temps stay in the mid to low 80's when in battlefield 4 on ultra. A cooling pad also helps when you want to game as well, even though its not needed when doing word or internet.
This thread is dedicated to this laptop and is actually full of awesome information even though the op decided to return it. If you are really interested in this small form factor laptop then I suggest you look at the p35w v3 cf4 as its the same chassis but with the 970m so it stays cooler and its cheaper and comes with an ssd wile giving great fps in almost every game on ultra
(information taken form the forum from various posts)
http://forum.notebookreview.com/threads/gigabyte-p35x-v3-owners-lounge.764645/