On 2011-02-20 15:15 +0100, Carlo Stemberger wrote:
> Package: xserver-xorg-video-nouveau
> Version: 1:0.0.15+git20100329+7858345-5
> Severity: normal
>
> This bug causes an annoying "black flash" every 30 seconds.
The flashing might be due to upowerd polling the DRM devices with this
frequency, see #613745. Try disabling upowerd, or downgrade upower to
the version in squeeze.
Cheers,
Sven