Screen flicker on external monitor

Gen2ly · 2010-07-22 00:47:10

Has anyone had any experience with screen flicker on an external monitor? I connected my laptop to an external monitor and I get consistent flicker on the whole screen. If anyone can help, or could help pointing me to website etc. I'd appreciate it.

0mark · 2010-07-22 08:56:22

Sadly i couldnt help, but i have (possibly) the same problem. If your laptop has some a little older intel onboard graphics, we have the same porblem. It occured for some month ago with a driver upgrade. I have done some search then, but found nothing helped me, but some people reported some tweaks that helped them (none of them helped me). Since the problem is known for month now, i doubt that intel has a high priority on fixing this.
Then my external Monitor broke during a power failure, and i lost mostly my interest in the problem.

JackH79 · 2010-07-22 09:21:27

If it's not software realted, you could try and check:
- to connect the screen to another machine? If you get the same flicker, could be that the screen's capacitators are broken.
- whether it's the cable (I know it's obvious, but ... )

Gen2ly · 2010-07-22 17:13:06

Good suggestions guys I'll put out some more information. The cable is ok (good thought to check for it). I plugged my vga cable to my tv and do not get the screen flicker. Also I'm using the ati driver which possibly has the same problem as the intel, one. I configured my xorg.conf as describe in the wiki xrandr page:

http://wiki.archlinux.org/index.php/Xra … _xorg.conf

One thing that I noticed that is a bit odd is the xrandr reports the display rate as 60.1. I've never seen this before so right now I'm thinking that it has to do with that.

xrandr 
Screen 0: minimum 320 x 200, current 1440 x 900, maximum 1440 x 1440
VGA-0 connected 1440x900+0+0 (normal left inverted right x axis y axis) 410mm x 257mm
   1440x900       60.1 +   75.0* 
   1400x1050      74.9     60.0

Still up the river so any more suggestions would be definitely appreciated.

JackH79 · 2010-07-23 01:34:24

Not that odd. My external screen always comes up with 59.9 Hz. No idea why. Guess it could be a rounding error in a calculation or something. Never led to flicker on my screen though.

But: according to your xrandr output you're running your screen at 75.0 Hz instead of the screen's preferred (the '+') mode of 60.1. Have you tried to switch it to that refresh rate. That could be the cause of your trouble.

gpmr · 2010-07-23 10:09:40

Had exactly the same problem. I was able to solve the problem by connecting the external screen to the DVI port of my laptop (DELL LATITUDE D830 + docking station). Changing the refresh rate didn't change anything in my case.

Conclusion: all that inconvenient flickering was caused by the VGA port.

Arch Linux

#1 2010-07-22 00:47:10

Screen flicker on external monitor

#2 2010-07-22 08:56:22

Re: Screen flicker on external monitor

#3 2010-07-22 09:21:27

Re: Screen flicker on external monitor

#4 2010-07-22 17:13:06

Re: Screen flicker on external monitor

#5 2010-07-23 01:34:24

Re: Screen flicker on external monitor

#6 2010-07-23 10:09:40

Re: Screen flicker on external monitor

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