I've noticed "crashing cards" too, when dumping old scenes or meshes and replacing with new ones, but only when they were large compared to the VRAM available. Sometimes a system reboot was the only remedy.
I'm straying from the original topic, but connected to the above post, another "disaster" I will never repeat again was running my dedicated-to-Octane GTX560 on a render with plenty of VRAM to spare, and running another small render on my 260, which has to do double time carrying out Windows functions. I had other apps running at the time, including Firefox when my system completely locked up. CNTL/ALT/DEL would not bring up Task Manager so I was pretty well screwed. So I just turned the machine off and let it reboot. Unfortunately, even though I had an Internet connection, I could not get online. Also some programs settings became corrupted or simply refused to run. Diagnostics found no problems so the only solution that worked was to disable the network card, shutdown, unplug my router and cable modem, plug them back in, reboot and re-enable the network card. I think what happened was that when the lock-up occurred and I shutdown, the network card was left in a bizarre state with Windows that it could not recover from. This affected ALL apps that required access to the Internet. Even Task Manager could not stop any tasks that were attempting to gain Internet access. So by disabling the network card, I was able to get Windows to let go of it. I really don't know, but what I think started all of this was that the 560 was sending data back to the motherboard that needed to go to the screen, but the 260 which runs my monitor was running an Octane job, too, and I think Octane got confused. It is also possible that even though Octane showed that I had plenty of VRAM left on the 260 does not necessarily mean it had enough when Windows was using it, too.
So my MO (for now, anyway), is never run any GPU render jobs on the card that also runs Windows display functions, while another GPU renders. Leave Octane to render-dedicated GPUs.
Win7 | Geforce TitanX w/ 12Gb | Geforce GTX-560 w/ 2Gb | 6-Core 3.5GHz | 32Gb | Cinema4D w RipTide Importer and OctaneExporter Plugs.