Thread: xrandr - add resolution mode

hello, have computer connected tv vga cable. tv resolution writen hd ready (not sure means). anyway, vga input tv has options xga (1024x768) , wxga (1280x768). on computer have lubuntu 11.10. in automaticaly detected resolutions no option of 1280x768, setting these commands @ startup:

# gtf 1280 768 59.9
xrandr --newmode "1280x768_59.90" 80.00 1280 1344 1480 1680 768 769 772 795 -hsync +vsync
xrandr --addmode vga-0 1280x768_59.90
xrandr -s 1280x768_59.90

works ok , resolution 1280x768. trouble seem not resolution. when draw square, looks rectangle (it wider should be). looked @ other computer connected same tv hdmi. windows 7 on @ resolution automaticaly detected 1280x720. decided try resolution on first computer well. run these commands:

# gtf 1280 720 59.9
xrandr --newmode "1280x720_59.90" 74.36 1280 1336 1472 1664 720 721 724 746 -hsync +vsync
xrandr --addmode vga-0 1280x720_59.90
xrandr -s 1280x720_59.90

unfortunately dont work. when execute last command, screen become black (i think xserver falls). when restart lightdm, working again, not in 1280x720.

please give me advice, how solve this? thank

vga in linux seems clueless optimum video modes. dvi communicates better modes capable of , uses best mode. perhaps can shed light on video mode, legacy ati x1300 displaying native 1280x720 on old apex hdtv ready 27" lcd.

code:

from /var/log/xorg.0.log  (ii) radeon(0): supported standard timings: (ii) radeon(0): #0: hsize: 1280  vsize 1024  refresh: 60  vid: 32897 (ii) radeon(0): #1: hsize: 1024  vsize 768  refresh: 60  vid: 16481 (ii) radeon(0): #2: hsize: 800  vsize 600  refresh: 60  vid: 16453 (ii) radeon(0): #3: hsize: 1280  vsize 720  refresh: 60  vid: 49281 (ii) radeon(0): supported detailed timing: (ii) radeon(0): clock: 74.5 mhz   image size:  597 x 336 mm (ii) radeon(0): h_active: 1280  h_sync: 1344  h_sync_end 1472 h_blank_end 1664 h_border: 0 (ii) radeon(0): v_active: 720  v_sync: 723  v_sync_end 728 v_blanking: 748 v_border: 0 (ii) radeon(0): ranges: v min: 56 v max: 75 hz, h min: 30 h max: 64 khz, pixclock max 110 mhz (ii) radeon(0): monitor name: nexgen nl27 (ii) radeon(0): serial no:  (ii) radeon(0): edid (in hex): (ii) radeon(0):         00ffffffffffff0038b8920001000000 (ii) radeon(0):         300c0103813c22782a7e5ca554449924 (ii) radeon(0):         12484bafce0081806140454081c00101 (ii) radeon(0):         0101010101011a1d008051d01c204080 (ii) radeon(0):         350055502100001c000000fd00384b1e (ii) radeon(0):         400b000a202020202020000000fc004e (ii) radeon(0):         455847454e204e4c3237200a000000ff (ii) radeon(0):         00200a20202020202020202020200027 (ii) radeon(0): panel infos found ddc detailed: 1280x720 (ii) radeon(0): edid vendor "nex", prod id 146 (ii) radeon(0): printing probed modes output dvi-0 (ii) radeon(0): modeline "1280x720"x59.9   74.50  1280 1344 1472 1664  720 723 728 748 -hsync +vsync (44.8 khz) (ii) radeon(0): modeline "1280x1024"x60.0  108.00  1280 1328 1440 1688  1024 1025 1028 1066 +hsync +vsync (64.0 khz) (ii) radeon(0): modeline "1280x720"x60.0   74.48  1280 1336 1472 1664  720 721 724 746 -hsync +vsync (44.8 khz) (ii) radeon(0): modeline "1024x768"x75.0   78.75  1024 1040 1136 1312  768 769 772 800 +hsync +vsync (60.0 khz) (ii) radeon(0): modeline "1024x768"x70.1   75.00  1024 1048 1184 1328  768 771 777 806 -hsync -vsync (56.5 khz) (ii) radeon(0): modeline "1024x768"x60.0   65.00  1024 1048 1184 1344  768 771 777 806 -hsync -vsync (48.4 khz) (ii) radeon(0): modeline "800x600"x72.2   50.00  800 856 976 1040  600 637 643 666 +hsync +vsync (48.1 khz) (ii) radeon(0): modeline "800x600"x75.0   49.50  800 816 896 1056  600 601 604 625 +hsync +vsync (46.9 khz) (ii) radeon(0): modeline "800x600"x60.3   40.00  800 840 968 1056  600 601 605 628 +hsync +vsync (37.9 khz) (ii) radeon(0): modeline "800x600"x56.2   36.00  800 824 896 1024  600 601 603 625 +hsync +vsync (35.2 khz) (ii) radeon(0): modeline "640x480"x75.0   31.50  640 656 720 840  480 481 484 500 -hsync -vsync (37.5 khz) (ii) radeon(0): modeline "640x480"x72.8   31.50  640 664 704 832  480 489 492 520 -hsync -vsync (37.9 khz) (ii) radeon(0): modeline "640x480"x59.9   25.18  640 656 752 800  480 490 492 525 -hsync -vsync (31.5 khz) (ii) radeon(0): modeline "720x400"x70.1   28.32  720 738 846 900  400 412 414 449 -hsync +vsync (31.5 khz)   efflandt@efflandt-lucid64:~$ gtf 1280 720 60    # 1280x720 @ 60.00 hz (gtf) hsync: 44.76 khz; pclk: 74.48 mhz   modeline "1280x720_60.00"  74.48  1280 1336 1472 1664  720 721 724 746  -hsync +vsync  efflandt@efflandt-lucid64:~$ gtf 1280 720 59.9    # 1280x720 @ 59.90 hz (gtf) hsync: 44.69 khz; pclk: 74.36 mhz   modeline "1280x720_59.90"  74.36  1280 1336 1472 1664  720 721 724 746  -hsync +vsync  efflandt@efflandt-lucid64:~$ cvt 1280 720 # 1280x720 59.86 hz (cvt 0.92m9) hsync: 44.77 khz; pclk: 74.50 mhz modeline "1280x720_60.00"   74.50  1280 1344 1472 1664  720 723 728 748 -hsync +vsync

note cvt, without specifying hz, seems come numbers match optimum 59.9 dvi connection automatically uses, if cvt rounds description (in quotes) 60.00.

Forum The Ubuntu Forum Community Ubuntu Official Flavours Support Multimedia Software [lubuntu] xrandr - add resolution mode

Ubuntu