Crashes

Hello.
First of all, sorry for my english, it's not my native language.
I'm experiencing constant crashes. The game just freeze for 2 second and crash to the dekstop without any message. It happens quite often, mostly in delves and when I'm alt+tabing or changing graphics settings. During maps when I come back all mobs are dead, but I need to uncover fog of war again. I have better times when I can play for few hours without any crash. All my drivers are up to date except graphics card. Latest drive 416 is giving 5 fps in average less than 399.
My PC is quite new, only 2 weeks old, but those crashes also happening on my old laptop but less frequently.
My Rig:
Amd a5 2600 Stock
16GB RAM DDR4 3200 Mhz
GTX 1060 6GB
I have multithreading turned on. I heard that can be an issue but turning in off can give big fps drops below 60.

I fixed my issue for now. No crashes to desktop. I just reinstalled Nvidia drivers (Clean reinstall, not some quick ones) and I also uninstall my Avast antivrus and malware protection because It has some issues with Windows Defender. Then I clean my PC with CCleaner to make sure that all remaining files are deleted. I don't know which one of these 2 caused this but now I play for around 10 hours and nothing happend, but I don't wanna touch graphics settings for now. Alt+tab works fine on the other hand, lag spikes also don't cause crashes. Maybe it will give some use to someone with similar problem.

Ehh, still crashing, after a long while it crashed 10 times in an hour, even with multithreading off.