Second monitor shows desktop 'tiling' on ubuntu 12.04
 

Hi,

I've recently bought a Korean 27" 2560x1440 display, and have been having trouble trying to get it to work with my laptop (Toshiba portege r830-13c so intel integrated graphics), connected using an HDMI to DVI-D cable (monitor only takes dvi-d).

Originally the laptop cannot find any compatible modes for the monitor (maybe an EDID problem?), but after supplying a 2560x1440 mode to xrandr:

xrandr --newmode "2560x1440_60.0" 311.83 2560 2744 3024 3488 1440 1441 1444 1490 -HSync +Vsync

xrandr --addmode HDMI1 2560x1440_60.0

The monitor displays the extended desktop, but it oddly seems to be replicating the second monitor's workspace tiled over the screen...
Image for clarification: http://i.imgur.com/pLZXZ.jpg
I have no idea what could be causing this, so any help or suggestions would do the world of good..

Thanks,
Malfernion

Toshiba portege r830-13c specs say-

http://uk.computers.toshiba-europe.c...0-13C/1106028/

So 2560x1440 might be impossible. Have you tried a lower resolution, like 1920x1080?

Thank you for pointing that out..
Just tried your suggestion, using modes at 60hz and 59.9 the monitor displays with heavy artifacting.. I'm thinking things really aren't helped by using dvi-d to HDMI, as plugging the monitor dvi-d to dvi-d in a desktop with a discrete graphics card it worked perfectly straight away.

In theory a HDMI to DVI-D connector shouldnt have any effect. But its possible it is causing part of the problem.

If you've got the monitor running on another system, you could try creating an xorg.conf file, then copying the relevant monitor section to the laptop. But I'd doubt you will ever get 2560x1440, no mater what you do.