(In reply to comment #76)
>
> Since my last cold boot, I tried with unlimited clocks (reverted previous
> patches) with hangs almost at start. I tried again with stock 3.13-rc3 with
> spread spectrum disabled, and I also hit hangs when testing (without having
> to push the video card with heavy tests). So, for me, disabling spread
> spectrum may sometimes help, but it is not a real solution to this bug.
> 
> Sorry for bringing bad news.

Make sure you try on a cold boot.