[Solved] another flickering monitor problem

Question

Hi,
I hooked a new LED monitor to my laptop via a VGA cable but the sad
part is that the monitor flickers quite a bit. It's not a hardware
problem because I hooked the monitor to a windows box (using the same
VGA cable), and the monitor works perfectly well.
My laptop uses the video card ATI Radeon HD 3670. I'm currently using
the open source driver xf86-ati-video.
Here are a few things I've tried (many of them based from previous
posts) that I didn't have any success: to use the ATI's proprietary
driver (catalyst); to use xf86-ati-video-git; to disable KMS; to check
the output of xrandr (the preferred and the current mode match); and
to downgrade to older version of the xf86-ati-video. My archlinux box is
also upgraded.
I noticed the following patterns in my monitor flickering:
- it only happens with darker colors (no flicker when I open a white
  page for instance).
- the flicker is not limited to X. The virtual consoles also flicker.
  So I think that means that the cause of the flicker has nothing to
  do with Xorg.
- the flicker is vertical.
- The flicker does not occur when I'm at the GRUB menu.
Any suggestion of how I can solve this problem is more than welcome!
Cheers,
Last edited by falsum (2011-06-05 00:39:10)

Answer 1

karol wrote:
falsum wrote:I guess the problem was the VGA port of my laptop.
I'm really glad you solved it :-)
If you want, you can boot a liveCD / liveUSB and see if it has problems with your VGA too. If it runs OK, the problems may be related to your Arch setup.
If you can get another monitor with a VGA connector you can test it too - maybe your laptop is just jealous of the new shiny monitor ;P
These are good ideas. I get the same flickering with the ubuntu live cd but I didn't try with the arch live cd yet. As to other monitors, I still get the same flickering when I use a different monitor with a VGA cable.
I think you're right: my laptop must be getting jealous :-)