Hello to all, today i decided to share this since i bet there are many others who have this black screen problem: "nvidia drivers stopped working and has recovered" when they try to play games using Nvidia video cards thanks to the "bad" made drivers lately.
Personally i tried everything from upgrading and downgrading drivers to overclock and under-clock the GPU and nothing worked for me.
From what did i hear and read these problems are mostly because of the power saving the drivers try to make/change on the Nvidia video cards so i tried to give more power to the card using these 3 steps witch "worked" for me at least till now for the last two months:
1) Start --> Control Panel -> Power Options: Change to "High Performance" instead of the default "Balanced".
After this click "change plan settings" then click "change advanced power settings" and in this menu click PCI Express , "Link State Power Managment" and make sure this is set to "Off".
2) Open "Nvidia Control Panel" (C:\Program Files\NVIDIA Corporation\Control Panel Client) and at the option "Manage 3D settings" at "Power Managment Mode" make sure you change to "Prefer Maximum Performance" instead of the default "adaptive" option.
3) Right click the World of Warcraft icon (or your game icon) and select "Properties".
Select the "Compatability" tab and check the box for "Disable Desktop Composition" and click Ok.
After all these steps are done i suggest to reboot the PC so everything can apply good.
I don't know if this will solve your problems too but i certainly hope so, and i hope i was able to help out some of the players and boters out there stressed by this problem same as i was
Note: I solved this problem in Windows 7 ultimate, no idea if it works same way in others versions of Windows too but is worth a try.