I suspect the problem will be related to the fact that your system will switch from the nvidia graphics card to the low power Intel graphics when you remove the power cable.
Looking at your latest files the nVidia graphics driver is not the one on the support page.
View attachment 78311
Please try DDU again and then replace with the recommended one. It might be worth disconnecting from the internet when you make the change in case the system is automatically picking up a graphics driver from the internet before you have loaded the one you want. Obviously you will have needed to download the above driver file beforehand.