https://bugzilla.kernel.org/show_bug.cgi?id=94061
Bug ID: 94061 Summary: [radeon - Kaveri] dpm works badly - much to high power consumption compared to catalyst Product: Drivers Version: 2.5 Kernel Version: 3.14.x ... 3.19. Hardware: All OS: Linux Tree: Mainline Status: NEW Severity: normal Priority: P1 Component: Video(DRI - non Intel) Assignee: drivers_video-dri@kernel-bugs.osdl.org Reporter: abcdmail@freenet.de Regression: No
With all kernel versions >= 3.14 (I didn't test versions below), radeon / dpm consumes about 6 W more compared to catalyst in idle mode (X-server 1.15 / 1.16) with Kaveri graphics (AMD A10-7800 Radeon R7).
Idle mode: Xorg runs (KDE 4.11.x), screen saver off, static screen, load: 0.0
If the screen is turned off by X, the power consumption finally reaches the same level as with catalyst. It's raising immediately again at the moment the screen is switched on again by X.
Seams the lowest rate is never reached as long as even a static screen has to be drawn - but it should!