I installed relive 16.12.1 driver got code 43 error.
Reverted back to 16.11.5 work perfectly

Ps. My 470s were bios modded

Did you use DDU or windows rollback? Because AMD utility doesn't work and they mention it only in release notes for Pro cards:
http://support.amd.com/en-us/kb-articles/Pages/AMD-FirePro-and-Radeon-Pro-Software-Crimson-ReLive-Edition.aspx

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Using AMDCleanUpUtility.exe directly to uninstall the driver may not perform as expected

Juz use the latest ddu to uninstall 16.12.1, u will be fine

DDU is best. It is much better than the AMD clean utility. But make sure you reboot into safe mode to do the clearn up.

Yes, there is new DDU version for all of you who want to get rid of 16.12 driver

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Display Driver Uninstaller (DDU) V17.0.4.0 Released.

ChangeLog:

-Added support to AMD Crimson ReLive Edition 16.12.1