The GPU fan is louder, because there is no longer a PCI-E 1x bottleneck that holds back the GPU 
I dont really know if I have the same issue at n1salat, but here is my dxdiag. I am experiencing low framerates even at medium settings, something I do not believe I should be experiencing. It happens mostly in the campDxDiag.txt (71.3 KB).
What framerate are you experiencing? A 970m isnāt the greatest graphics card out there. The only reference I have is my pc with a (desktop) 970 and I get around 40 fps average. Changing the detail settings does not change my framerate (only the object render distance settings do). Remember this is an alpha and is not optimized for any configuration. Playing this game on a laptop is quite possibly not possible.
First Thing to Check: Bios Updateā¦
http://www.asus.com/DE/Notebooks/ASUS_ROG_G751JT/HelpDesk_Download/
Ver 210 is the newestā¦(yours: 202ā¦ initial releaseā¦so quite oldā¦)
Any Problems with other games???
If so, first check your used PCI-E Lanes via GPU-Z