It seems that Nvidia driver 436.30 has fixed Forza Motorsport 7, at least for me. I have played a few hours and no crash or stalls 
My pc spec:
OS: Windows 10 Home (64bit)
Motherboard: Asus Z270-P
CPU: Intel Core i7 7700K (4.2GHz)
RAM: Crucial 2x 8 Gb (2400MHz)
Graphic: Gigabyte GTX 1080Ti OC 11Gb
PSU: Inter-Tech Energon EPS-750W
Hope it will fix the game for you to