Driving the Dell U2713HM at 2650×1440 from the HDMI output of the Acer V3-571G

(TL;DR See the last paragraph for how to get the Dell U2713HM working on the HDMI output of the Acer V3-571G at 2560×1440 @ 50Hz.)

The Dell Ultrasharp U2713HM is a 27″ IPS panel with a resolution of 2560×1440. I recently acquired this monitor and wanted to connect it to my Linux-only Acer V3-571G i7 laptop, which only a VGA (D-SUB; max resolution 2048×1536) and an HDMI 1.4 output.

The monitor has been optimised to show the Dell logo. (image from the Engadget review I linked to above.)

HDMI 1.4 does support 2560×1440, but the HDMI 1.3 input on the Dell U2713HM does not. (The HDMI 1.4 input on the more expensive Dell U2713H does.) This means that we have to use either the DVI or DisplayPort inputs.

For 2560×1440 at 60Hz refresh rate, normal single-link DVI is not sufficient. One either needs dual-link DVI, which I don’t have, or one can use a cheap HDMI to DVI connector and tweak the timings of normal single-link DVI to supply 2560×1440 at a frequency that is as close as possible to 60Hz, but still fits within the available bandwidth.

Part of this tweaking is making use of reduced blanking, an optimization that can be done on LCD panels where there’s no electron beam (as is the case in CRTs) that needs time to be repositioned. In short, we can squeeze out more resolution and refresh from the same bandwidth.

NotebookCheck has a wealth of information on tweaking these timings. Unfortunately, the configuration they supply for 2560×1440 at 55Hz only caused flickering on my setup.

Fortunately, Linus Torvalds (just some guy who seems to know quite a bit about Linux šŸ˜‰ documented on Google+ his adventures getting such a monitor going under Linux, albeit with a 30Hz refresh rate. Fortunately, a commenter named Tim Small posted the timings he had generated with a hacked version of cvt!

Based on his timings, I could get my monitor going stably at 2560×1440 at 50Hz. Enter the following in a terminal:

xrandr –newmode "2560x1440_50.00_rb" 200.25 2560 2608 2640 2720 1440 1443 1448 1474 +HSync -Vsync
xrandr –addmode HDMI1 "2560x1440_50.00_rb"

When you enter after the second line, the monitor should switch to the 2560×1440 mode. After having done this, 2560×1440 appears as a selectable mode in the Ubuntu Displays app.

Ubuntu 10.10 x86_64 on your Dell E6410 with NVS 3100m GPU

Well howdy hoo! This is the fastest and most painless guide to installing Ubuntu 10.10 (Maverick Meerkat) x86_64 on your Dell E6410 laptop with NVS 3100m GPU.

More specifically, installing Ubuntu 10.10 on this specific hardware configuration poses two problems:

  1. Blank (black, no backlight) display when booting with the install media, or, if you manage to get Linux on the machine, with the installation itself.
  2. Blank (black, no backlight) display when resuming from suspend to ram after having installed Ubuntu.

Solving problem 1

  • Boot with the normal Ubuntu 10.10 x86_64 Desktop live disc. I usually do this from USB memory.
  • When you get to the first boot menu (“Try Ubuntu without installing”, “Install Ubuntu”, etc.), press F6 for other options, then ESC to kill the menu that appears. Move the menubar to “Try Ubuntu without installing”.
  • You can now edit the boot command-line. Replace “quiet splash” with “nouveau.modeset=0”
  • Press enter to boot into the live desktop, then install the whole business as per usual.
  • At the first boot after installation, press ‘e’ at the grub boot screen to edit the command line and again replace “splash quiet” with “nouveau.modeset=0”.
  • You should get all the way to the Ubuntu desktop.
  • Activate the NVidia drivers via System | Administration | Additional Drivers
  • Now edit /etc/default/grub, and replace “splash quiet” in the GRUB_CMDLINE_LINUX_DEFAULT with, you guessed it, “nouveau.modeset=0”.
  • Run “sudo update-grub” at the command-line.
  • Problem solved.

Solving problem 2

  • Edit the GRUB_CMDLINE_LINUX_DEFAULT variableĀ /etc/default/grub again. When you’re done, it should read (we’ve added the acpi_sleep bit at the end):
    GRUB_CMDLINE_LINUX_DEFAULT="nouveau.modeset=0 acpi_sleep=nonvs"
  • Run “sudo update-grub” at the command-line.
  • Problem solved.
  • (if you really want to know more about this, including several other more painful work-arounds, read this bug report)

Generally, I’m really impressed with the general slickness of 10.10 on this machine. What impressed me particularly, was that powertop reported about 14W of power consumption at idle on this out-of-the-box setup (disregarding the two tweaks above). It used to take much more effort to get that low.