Had a issue on last project in 12 as well, seems if I rendered my project to a MPEG2 DVD it would freeze about a fourth of the way through the render and never at the same spot, If I rendered the same project to Bluray It renderd normally...I basically had to disable the GPU and the render proceed normally...
Don't know if it's any help but I had a persistent V12 render-freeze issue (Win7 64 bit, GTX660) rendering to mpg2.
Tried a fix that I read somewhere on this forum --- changed RAM Preview from 200 (the default?) to zero but left GPU acceleration on. Has since rendered mpg2 OK on the three separate occasions I've needed to use it, up to 16 minutes project.
>Tried a fix that I read somewhere on this forum --- changed RAM Preview from 200 (the default?) to zero but left GPU acceleration on. Has since rendered mpg2 OK on the three separate occasions I've needed to use it, up to 16 minutes project.