AB may solve some issues with certain ease, but installing it may have impact on other apps using/accessing GPU drivers/configs.
Overall you should try to spend few hours or even days and find alternative solution(to using AB) as it may save you more time in the long run.
This AB stuff is just too fucking invasive and persistent for my taste.
Re bios mod: Look in my recent posts, you can find there all the numbers&info on what I do with 470s.
Drivers installed the way I like: 1) don't run crimson-whatever.exe, instead unzip it 2) open device manager and find your graphic adapters(should be not identified at this point) and choose there option to "update driver"-> select folder manually 3) repeat 2) if needed for other card/s
I using the BIOS mods in same way you do but after switching to Claymore 10.0 something strange happens with one rig - it does not work with config.txt imported from v9.8, cases:
1) system completely hangs during initialization
2) some cards do not start to hash at all (0.0MH speed)
3) some cards starts with slower speeds (for example 22MH/s or lower)
Checked via HWinfo - it shows similar voltages and frequencies (of course exept case 1).
So rolled this rig back to 9.8 which gives stable mining.