**System Information**
Windows 7 SP 1
Nvidia GForce 960
and Gforce 660 TI
**Blender Version**
Broken: 2.73a 2015-01-20 18:16
Worked: (optional)
**Short description of error**
Attempting to render an animated sequence exporting PNG files. With each "restart" of the animation export, I get about 10 files rendered with each attempt. The renders get progressively longer and eventually just freeze with the last render status bar full and does not progress to the next frame.
I attempted to select just the GForce 960 with the same result.
**Exact steps for others to reproduce the error**
Based on a (as simple as possible) attached .blend file with minimum amount of steps