[xf86-video-intel]monitor goes blank with fb compression on

[Jesse Barnes]

On Monday, January 14, 2008 9:15 am Anton Khirnov wrote:
> Hi,
> I have a FJS Amilo Pi-1505 laptop with GMA950 and I connect it to a
> NEC MultiSync FP2141 CRT monitor. The problem I'm having is that
> external CRT goes blank after about hour of work and only reboot fixes
> it. LVDS remains perfectly functional and VT works on both monitors.
> Restarting Xserver, reloading drm modules or playing with xrandr
> doesn't help, there's still nothing on the screen, though the monitor
> detects the signal with normal frequencies. Also absolutely nothing
> interesting appears in logs (dmesg and Xorg).
>
> Adding Option "FramebufferComperssion" "off" seems to fix it, but it's
> surely not optimal solution.
> Btw anyone care to explain, what is fb compression good for?

It's a power saving feature.  It saves power by reducing the amount of memory 
bandwidth needed to scan out the display.  Unfortunately, it has some usage 
restrictions and has been giving a few people problems.  I wonder if what 
you're seeing is related to 
https://bugs.freedesktop.org/show_bug.cgi?id=13418.  If that doesn't look 
similar enough, please file a new bug and I'll take a look.

Thanks,
Jesse