I have a new monitor, (the Dell U2515H) which I'm trying to drive at 2560x1440 resolution (just 30hz) over HDMI using only the onboard graphics on my machine (Intel HD4000 found in the ivy bridge CPU). My exact machine spec here.
I know it's possible because I've had it working once yesterday and once today. It just randomly appeared in my available screen resolution options. Yesterday it worked for a bit (~10 minutes?) then suddenly flipped back to 2048x1152 and the option for 1440 resolution disappeared. Today the option appeared and so I selected 2560x1440 which worked fine:
I then tried re-booting the machine in an effort to "persist" my preference, but after rebooting I hit this error message:
Full error message here if anyone is interested, but basically, it looks like it never tried 30hz.
On the right hand side of the screenshot you can see the output from xrandr so you can see that my option for 2560x1440 has disappeared again.
I've tried using xrandr to add the resolution manually but it doesn't work:
matt@beast:~$ gtf 2560 1440 30
# 2560x1440 @ 30.00 Hz (GTF) hsync: 43.95 kHz; pclk: 146.27 MHz
Modeline "2560x1440_30.00" 146.27 2560 2680 2944 3328 1440 1441 1444 1465 -HSync +Vsync
matt@beast:~$ xrandr --newmode "2560x1440_30.00" 146.27 2560 2680 2944 3328 1440 1441 1444 1465 -HSync +Vsync
matt@beast:~$ xrandr --addmode HDMI2 "2560x1440_30.00"
matt@beast:~$ xrandr --output HDMI2 --mode "2560x1440_30.00"
(screen flicks black for a moment but it just doesn't change the mode).
Any ideas what I can try next?
Update
I was able to get the edid information (thanks to the kind author of get-edid
):
Section "Monitor"
Identifier "DELL U2515H"
ModelName "DELL U2515H"
VendorName "DEL"
# Monitor Manufactured week 45 of 2014
# EDID version 1.3
# Digital Display
DisplaySize 550 310
Gamma 2.20
Option "DPMS" "true"
Horizsync 30-113
VertRefresh 56-86
# Maximum pixel clock is 300MHz
#Not giving standard mode: 1680x1050, 60Hz
#Not giving standard mode: 1920x1200, 60Hz
#Not giving standard mode: 1152x864, 75Hz
#Not giving standard mode: 1600x1200, 60Hz
#Not giving standard mode: 1280x1024, 60Hz
#Not giving standard mode: 1200x960, 60Hz
#Extension block found. Parsing...
revnum: 3
Modeline "Mode 16" 148.50 1920 2008 2052 2200 1080 1082 1087 1125 +hsync +vsync
Modeline "Mode 0" 241.50 2560 2608 2640 2720 1440 1443 1448 1481 +hsync -vsync
Modeline "Mode 1" 148.500 1920 2008 2052 2200 1080 1084 1089 1125 +hsync +vsync
Modeline "Mode 2" 74.250 1920 2008 2052 2200 1080 1082 1087 1125 +hsync +vsync interlace
Modeline "Mode 3" 74.250 1280 1390 1420 1650 720 725 730 750 +hsync +vsync
Modeline "Mode 4" 27.027 720 736 798 858 480 489 495 525 -hsync -vsync
Modeline "Mode 5" 27.027 720 736 798 858 480 489 495 525 -hsync -vsync
Modeline "Mode 6" 27.027 1440 1478 1602 1716 480 484 487 525 -hsync -vsync interlace
Modeline "Mode 7" 27.000 1440 1464 1590 1728 576 578 581 625 -hsync -vsync interlace
Modeline "Mode 8" 25.200 640 656 752 800 480 490 492 525 -hsync -vsync
Modeline "Mode 9" 74.250 1920 2448 2492 2640 1080 1082 1089 1125 +hsync +vsync interlace
Modeline "Mode 10" 148.500 1920 2448 2492 2640 1080 1084 1089 1125 +hsync +vsync
Modeline "Mode 11" 27.000 720 732 796 864 576 581 586 625 -hsync -vsync
Modeline "Mode 12" 74.250 1280 1720 1760 1980 720 725 730 750 +hsync +vsync
Modeline "Mode 13" 74.250 1920 2558 2602 2750 1080 1084 1089 1125 +hsync +vsync
Modeline "Mode 14" 74.250 1920 2448 2492 2640 1080 1084 1089 1125 +hsync +vsync
Modeline "Mode 15" 74.250 1920 2008 2052 2200 1080 1084 1089 1125 +hsync +vsync
Modeline "Mode 17" 74.25 1920 2008 2052 2200 540 542 547 562 +hsync +vsync interlace
Modeline "Mode 18" 74.25 1280 1390 1430 1650 720 725 730 750 +hsync +vsync
Modeline "Mode 19" 27.00 720 736 798 858 480 489 495 525 -hsync -vsync
Option "PreferredMode" "Mode 16"
EndSection
It looks like the mode I want is "Mode 0" so I tried to set that using xrandr (was that the correct thing to do?) but it doesn't seem to work:
matt@beast:~$ xrandr --newmode "2560x1440_47.43" 241.50 2560 2728 3000 3440 1440 1441 1444 1480 -HSync +Vsync
matt@beast:~$ xrandr --addmode HDMI2 "2560x1440_47.43"
matt@beast:~$ xrandr --output HDMI2 --mode "2560x1440_47.43"
xrandr: Configure crtc 0 failed
I can see the 2560x1440 option in "Screen Display" settings but I just get this error message:
Now what can I try?
/etc/X11/xorg.conf
but it doesn't mean that the driver will agree with it.