As for WHEA_UNCORRECTABLE_ERROR, here's what I recommend doing:
1) Turn the machine off and unplug it
2) Press and hold the power button for three seconds to drain all remaining power
3) Remove the graphics card from the system
4) Make sure that there is not visible damage to the PCIe connector
5) Put it back in
6) Start the machine up again
7) Use Display Driver Uninstaller to remove the current display drivers
8) Restart
9) Download and install the newest manufacturer drivers for your card
http://www.guru3d.com/files-details/display-driver-uninstaller-download.html
http://www.geforce.com/drivers