On Wed, Feb 25, 2009 at 2:12 PM, Gilad Arnold <arn...@cs.berkeley.edu> wrote: > Hi, > > I've been running Xorg with Gentoo Linux on my T40/T41 for a while now. > In the past I was able to use my DVI monitor to its full 1920x1200 > resolution with hardware acceleration using the open-source radeon > driver (single output mode, the laptop's LCD was disabled). However, > since the upgrade to Xorg 1.3 with the new XRandR capabilities, I'm > having trouble getting my DVI monitor to work properly. > > Specifically, xrandr is now reporting 4 different connections: LVDS (my > laptop's LCD), VGA-0, DVI-0 and S-video. With the LVDS running at > 1400x1050, my DVI stays blank (not sure if it is getting a signal at > all) at any resolution beyond 1680x1050, namely 1600x1200 or 1920x1200. > Moreover, even at 1680x1050, my picture is not very "stable": at times > of heavier video / CPU / memory usage (e.g. when scrolling a web-browser > page with the mouse, or when running a CPU/memory intensive program) my > DVI would go blank; sometimes picture is restored after a second or two, > but sometimes it stays blank and has to be reset (the '--off' option in > xrandr, then on again). Only at 1400x1050 (same as the LVDS resolution) > do I get a steady and reliable performance from my DVI. Clearly, this > defeats the purpose of using an external monitor at all... ;-) > > Some more details: the VGA-0 port works fine with the same monitor > (using the RGB port) and I am able to use the 1920x1200 mode flawlessly. > The picture quality is inferior to DVI, however, so this is not an ideal > configuration as well. > > Inspecting the Xorg log file I cannot spot anything peculiar that might > provide any hint: the radeon driver detects the hardware correctly and > is able to start it with hardware acceleration. I did not try switching > to fglrx yet. > > My suspect is that something is quirky between the xrandr module and the > radeon driver: either the former is assuming something about the > capabilities of the latter that cannot be supported (e.g. running 3 > displays with high resolution at the same time), or the latter is not > managing the hardware correctly (e.g. video memory conflicts/overflows, > etc). > > My configuration: Xorg server 1.3.0.0-r6 with Xorg ATI Drivers (radeon) > 6.10.0. I'm using the Xorg DRM module. lspci reports a Radeon R250 > (Mobility FireGL 9000) rev 02 and the Xorg log file confirms this. > > I would appreciate any hints on where I should look and what to check. > If my configuration is inherently not supported by the newer Xorg, then > I might rollback to an older version (although I do like the new xrandr > capabilities). Also, if fglrx works better then that's an option > (although I like it much less that using the open-source driver). > > Thanks for your help!
Sounds like display underflow. Try disabling the LVDS if you aren't using it. Another option is to increase the priority of the display controllers: Option "DisplayPriority" "HIGH" Alex _______________________________________________ xorg mailing list xorg@lists.freedesktop.org http://lists.freedesktop.org/mailman/listinfo/xorg