I thought it would be my graphics card also with all the problems that are occurring with the GTX 550 Ti atm, however when I was still on 10.8 I backed up the AppleHDA.kext. When updating to 10.8.2, I need to safe boot if I use the standard 10.8.2 AppleHDA, MultiBeast kext or the alpha version.
I have just installed my backup from 10.8 and yes I have no working audio, however I am able to boot! Before replacing the kext I tried GE=No etc. I believe we both looked at the same page on mountain lion audio, I made a short guide for ALC662 - are there the same edits I can apply to this AppleHDA from 10.8 instead of using the 10.8.2 kext?
EDIT
Strange things happening, I was able to boot once with 10.8 AppleHDA however after that no joy. I tried deleting AppleHDA and I still have my problem of not booting, so it's not that and as you say, I do believe it is the graphics. However how was I able to boot perfectly that once?
last line of verbose is:
considerRebuildOfPrelinkedKernel com.apple.kext.OSvKernDSPLib triggered rerebuild
What does that mean?