I'm on all latest version of both software:
- Armoury Crate: 2.6.14.0
- GPU Tweak II: 2.1.7.1 (from Geeks3D official download)
Before upgrading to latest Armoury Crate version, GPU sliders under manual mode would be grey out as they are controlled by GPU Tweak II. But now, these two software just don't talk with each other any longer...
Very annoying bug...