We were not able to reproduce this issue. We tested on a clean build of Windows 10/7, fully updated no other software installed other than the latest driver and the clock speeds behave as they should.
We will take another look at the issue if we get more reports.
If anyone experiences this issue, please provide a summary of your issue and your can provide your full system specs, as well reproduction steps.
A lot of people two years are reported about this mistake, and you hide, even at your forum is full of messages, the last working driver without uvd of a mistake 16.7.2
All, i've been stumped by this UVD clock state issue for a long time, and as a result i've continued to stay on 16.7.2 to allow idle clocks and boost clocks. However, today, i discovered how to restore access to all clock states on 18.5.1. I had a program in my task bar called NokiaSuite - yes i'm still kicking a Nokia phone. When running this app, my GPU would only use UVD low and UVD high clock states. Upon closing it my clocks went immediately to idle 300/150. Opening up a 3D application now brings up Boost clocks. I recommend to anyone still experiencing this issue to try looking for applications and killing background software that might be tasking the GPU by stealth like NokiaSuite. What's unclear is what has changed from 16.7.2 to later driver versions that leads to this different clock state behavior in relation to NokiaSuite. FYI, my GPU is an R9 270.
Software i've identified so far that seems to cause undesirable clock state behavior includes:
NokiaSuite v3.8.54 - when loaded in taskbar, the GPU will only utilise UVD clock states.
AMD UVD Decoder (13.3) - video playback with this decoder leaves clocks locked at UVD low (450MHz) after quiting video player. Alternative decoders such as Microsoft DTV-DVD Video Decoder and LAV Video Decocer test good, allowing 300/150 after video playback is discontinued.