Computer shuts down after a delay, using GTX 750 Ti and driver v346.35

Hey,

I recently installed a GTX 750 Ti on my machine. I was previously using GTX 550 Ti.
Since the current drivers provided with Ubuntu 14.04 did not support the new card, I installed the 346.35 driver from the xorg-edgers PPA.

The card now works, with a few issues:

  1. Whenever I shut down my machine, the signal to the monitor stops immediately, but the computer doesn't shut down. It shuts down automatically after about 10 seconds when a beep sounds. It doesn't feel correct.
  2. At one point when I booted my machine, it reached the Ubuntu desktop, but the screen was tinted red. The computer then restarted itself. The GRUB screen after the restart was also tinted red. After I restarted it manually, everything seemed to work fine. This only happened once. I'm wondering if this is an issue with the drivers, or the card.

Here is the output of nvidia-bug-report.sh. I did not run X in verbose mode. It can be provided on request.