Yesterday Nvidia launched a new set of drivers for their GeForce graphics cards, and it hasn't been the smoothest release so far. Many users have reported issues with the 364.47 build, particularly with the installer, causing Nvidia to quickly release a fix that you should install instead.
The main issue with the 364.47 drivers concerned its installation process, with some users experiencing a crash during the express installer that breaks their system. As the crash would then prevent affected users from booting into Windows, they'd have to either boot into safe mode and roll back to a previous driver version, or revert to a previous point using system restore.
Nvidia became aware of the issue shortly after users posted about their struggles on Reddit and other forums, and has released a new driver that includes a fix. Version 364.51 is still in beta at the moment, pending WHQL approval from Microsoft, but you should grab this version instead of 364.47 to ensure there's no issues during the installation process.
Aside from the fixes to the installer, the 364.51 driver is identical to 364.47 in its feature set.
On a less critical note, The Tech Report has discovered that the high-refresh-rate power bug that plagued earlier versions of Nvidia's GeForce driver has appeared once again, at least in version 364.47. Using an Asus PG279Q, a GTX 980 Ti, and a refresh rate of 135 Hz, the site managed to get the GPU idling at 925 MHz, which is well above the standard idle clock speed of 135 MHz.
The increased clock speed at higher refresh rate causes a pretty significant increase in idle power consumption. The test system used by The Tech Report rose from around 85W to around 140W due to the issue, which will have an effect on a user's power bill over time. Hopefully Nvidia can identify the issue and roll out an update in the near future.