If you had a working installation before you did what you did I hope you make a back-up with Time Machine.
If you are unable to get past kernel panic with boot flags then you either have to reinstall the OS or restore your last stable installation from Time Machine, my preference.
With hackintoshes in particular, but also with Apple hardware (come see my Mini), OS crashes happen and it is just easiest to restore from Time Machine. Even with Adobe or Microsoft software registration remains intact. At least it has for me.
Kernel panic indicates a fundamental mis-step in the initial configuration/installation and is usually not caused in my experience by changing audio or network settings. But I guess it could.
Many audio problems in my experience can be solved by using an earlier version of Multibeast because sometimes the latest versions are more problematic for your particular hardware and if your system is working stably there is no reason to look for trouble.
Be sure you have identified the correct onboard audio for your motherboard, with which Gigabyte I assume is a Realtec whatever. Installing the wrong audio software should not, in my experience, result in kernel panic, the audio just won't work. Although many users have good results with Voodoo I have not but it might work for you. You may have to experience with the DSDT or not settings.
You have to reboot after installing the audio drivers/kexts. If the speaker icon is not grayed out then it works.
I have been doing this since Mountain Lion with unlocked processors and ATI graphics cards: with a little research it all works. The tools here are excellent. I was astounded when I switched recently to an Nvidia card. It simply worked without having to change settings in Multibeast.
