I got my new card yesterday (ASUS HD7970-DC2-3GD5) and have been trying it out since then.
I have a small problem however. If I go into GPU Tweaks settings and enable "Overclocking range enhancement" the voltage is still stuck on 1178-1188 mV while both GPU clocks and memory clocks get unlocked (can move past 1125MHz on GPU and 6300MHz on memory).
I have been looking around a few times, enabling and disabling and such but I can't get it to unlock.
Using Catalyst 12.4 WHQL and GPU Tweak 22.214.171.124.