Arch Linux

pieterv

Member

Registered: 2014-08-24

Posts: 28

Weird colors, wrong color depth on external video output (KDE)

I'm having some issues connecting a monitor as external display through my mini-dvi port on a Lenovo T440s laptop.

As shown in the picture linked below, the colors are awfully wrong. It's seems like 8 bit color depth. In the picture, I'm running both displays unified.

http://i.imgur.com/zV7LPJ1.jpg

I'm running up to date KDE. Kernel 4.7.2-1.
Xorg log: http://pastebin.com/pY8UEhPc
dmesg: http://pastebin.com/GNh4n3eb
lspci: VGA compatible controller: Intel Corporation Haswell-ULT Integrated Graphics Controller (rev 0b) (prog-if 00 [VGA controller])
i915

I don't have much custom config. This arch install is rather fresh. 3 months ago I did a fresh install. Before that, it used to work.

Another thing, perhaps related: today I have tried hooking up a projector on the VGA port, and my laptop didn't even see it (did not appear in kscreen, not mentioned in xrand)

Most likely it's not the hardware. I have tried booting in windows and the external display works just fine.

Could anybody point me in the right direction? Thanks.

Last edited by pieterv (2016-09-06 22:18:53)

abhijitt

Member

Registered: 2016-04-15

Posts: 6

Re: Weird colors, wrong color depth on external video output (KDE)

Hi,
I am facing a similar issue - not sure if it's the same problem (posted here).
An image that is supposed to look like this looks like this.
Were you able to resolve it?

pieterv

Member

Registered: 2014-08-24

Posts: 28

Re: Weird colors, wrong color depth on external video output (KDE)

I never got it solved and gave up. Right now, it's also not possible to test again. Our problem seems very similar!!

Last edited by pieterv (2017-04-24 13:40:16)