Seems that the latest NVidia display drivers 196.75 have some issues, mostly relating to the control of the on board cooling fan. Its effects could cause the fan to malfunction or even stop. If this is true, it could really cause some real damage to your NVidia display cards.
If you're using this version of the drivers, please downgrade to the previous working drivers (196.21) immediately. Below is a quote from the NVidia official site.
196.75 Alert!
We are aware that some customers have reported fan speed issues with the latest 196.75 WHQL drivers on NVIDIA.com. Until we can verify and root cause this issue, we recommend that customers do not download this driver. Instead, please stay with, or return to 196.21 WHQL drivers. Release 196.75 drivers have been temporarily removed from our website and we also are asking our partners and others to remove temporarily this 196.75 WHQL driver as well.
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