Strange Viewport Bug

Hello there,
I have a quite annoying issue with my viewport. Everything was fine till now and suddenly the main viewport pane in the middle (where you can see the Figures, props etc.) went completely grey. Everything else was fine before. It seems that I can even klick on the Figures (even if I can't see what I am doing). Sometimes I see something, when I play with the panes. Minimize and maximize them, but it only lasts until restart and then everything is grey again. I really don't know how to fix that. My Laptop is very good. Acer Predator, 16 gb ram, GeForce 1050Ti, so the specs shouldn't be a problem at all. Is there anoyone else who run into this strange Problem and is able to tell me how he fixed it? Help would be much appreciated. I don't really want to reinstall Daz again, since I don't know how to save all my content and links properly, so that it work as it is now after the reinstall.
Best regards
Comments
Is it also grey in a screenshot? Are you sue that DS is using the nVidia GPU and not the GPU on your CPU (if there is one)? That would, I blieve, be listed in the nVidia Control panel which you can launch by right-clicking on the desktop.
Thanks for your fast reply :) Yes, I set the Nvidia GPU as default. Already checked that. I set the viewport to default and now I see the pane, but it doesn't respond. Or at leat it does, but I can't see it. I have no visual feedback, even if I can klick and select the Figures as usual.
Try holding down the ctrl key and pressing 9 - that should switch to Texture Sahded mode, if it has been set to something else (you can also use the sphere icon just to the left of the camera/view picker at top-right, assuming those controls are showing).
Viewport was always in texture shade mode. Checked that too. Updated my drivers recently, but nothing changed. Oddly, if I set the integrated graphics Card as default, then of course Daz doesn't work very well, but Viewport works better. And strangely sometimes Daz resets itself to use the Intel graphics card, which it shoudn't use... I often have to change that manually in the Nividia Control Panel and have to set it to use the right GPU.
All of that seems very strange, but I can work in one single setup. If I open or close one Pane, the viewport stops responding. If I switch everything back, then it works again. (Don't know for how long, but at the moment it's the only way I can work with Daz). The viewport isn't responding anymore then, sometimes it switches to grey, sometimes I have strange artifacts of pervious panes and viewports I closed and opened (see pic).