I had to make some DVDs for one of the high school's productions. My new edit box is an i7-5960 with AMD R9 290x GPU.
Source files were Canon MXF from a Canon XF300, 50 Mb/second, 4:2:2.
Vegas 13 Main Concept MPG2 renders crashed ("Vegas has stopped working") on 4 of the 10 files.
Since it been frequently mentioned here that MC MPG2 doesn't work with R9 290 GPUs, I didn't think about turning off GPU until I was really pulling the last of my hair out. Turned it off, restarted Vegas, MC rendered like a champ for all 10 files.
Even if it doesn't get any functional use out of the R9, it must still be touching it some way or another.