Playing around with my multi-monitor setup caused the multi-GPU (SLI) setting to disable. It all started when I was exploring whether it was possible to span a game across multiple monitors.
I have Dual-EVGA 590 GTX HydroCopper video adapters (which is effectively a quad-GPU setup). I’m running NVIDIA driver version 301.42 with DirectX 11. My motherboard is an ASUS Maximus IV Extreme with a Intel Core i7 2600K CPU (Sandy Bridge).
I selected NVIDIA Control Panel > Configure Multi-GPU, Surround, Phys-X > Span displays with Surround
It accepted the change, and then when I tried to run several games it didn’t work. (The reason is because my 3rd monitor is not the same size as all the others, which is an obvious requirement, but one I wasn’t aware of until I started researching that problem.)
When I changed back to Maximize 3D Performance, the computer BSOD (Blue Screen of Death) and my multi-hour recovery process began.
After figuring out how to uninstall the drivers cleanly, re-install, I was able to re-enable Multi-GPU support (so long as I only had a single monitor connected). As soon as I connected a second or third monitor, the computer would bluescreen. The fact that it happens on-demand means I should be able to get ahold of EVGA support and get them to diagnose the problem.
So, for now, if I want multi-monitor, I have to disable Multi-GPU support, then connect the monitors.
If I want Multi-GPU support, I have to disconnect all the monitors, then enable Multi-GPU.
Multi-GPU with multiple monitors results in BSOD.