Question Dual 1080ti make win10 very unstable and not responsive

Oct 20, 2019
Hi guys, I got some problems with my set up.
I have 2 Asus Rog Strix 1080ti, I have tested them on my pc and they work good. and also test in 3d mark, give me 10000+ score, and everything works perfectly, but when I stack them together, the win 10 system became very laggy, not responsive, and frequently black screen(recover in few seconds, sometimes I need to turn off and turn on my screen to make it work) Chrome not responding frequently, when I do some rendering, it gets worse, software not responding and crash frequently. I don't know what's the cause, I used Nvidia Experience download studio driver(always keep the latest driver), I also try game driver, not working as well. And my mouse frequently not responding when I use dual GPU. I have no idea. this is frustrating.
I test my GPU individually today and the system performed well.
It could not be a power issue since I am using a good 1000w PSU.
The rendering program I am using is Blender.
CPU: AMD 3900X
anyone who has tips or suggestions, please help me out!