Victor, I made some notes on a similar issue some time ago when I had an issue with a monitor that would come up correctly as 1280x1024 if I used a DVI cable, but would come up with 1024x768 if I used a VGA cable. Here's what I have -- this was for Dedora a few releases ago: ------------------------------------------------ On SouthPole, if the screen resolution doesn't come up as 1280x1024, then as root: use xrandr to get the display name: # xrandr Screen 0: minimum 320 x 200, current 1024 x 768, maximum 2048 x 2048 VGA1 connected 1024x768+0+0 (normal left inverted right x axis y axis) 0mm x 0mm 1024x768 60.0 800x600 60.3 56.2 640x480 59.9 use cvt to get new mode settings: # cvt 1280 1024 # 1280x1024 59.89 Hz (CVT 1.31M4) hsync: 63.67 kHz; pclk: 109.00 MHz Modeline "1280x1024_60.00" 109.00 1280 1368 1496 1712 1024 1027 1034 1063 -hsync +vsync Then enter the following both interactively (to test it) and add it to /etc/gdm/Init/Default for reboots. xrandr --newmode "1280x1024_60.00" 109.00 1280 1368 1496 1712 1024 1027 1034 1063 -hsync +vsync xrandr --addmode VGA1 1280x1024_60.00 xrandr --output VGA1 --mode 1280x1024_60.00 These get added right after the PATH and OLD_IFS lines in the Default file. ----------------------------------------------------- I found with a later version of Fedora that the file to which to add this is no longer at that location, but I don't know what the correct one is, since I no longer have the issue. More recently I am also using a TV as a monitor -- I had to jump through some hoops to disable overscanning on the HDMI port used by my computer. Oversanning apparently improves a broadcast picture, but for a computer you lose the edges of the display if it's enabled. I hope this helps you out. Richard Wilson On Wed, Feb 28, 2018 at 11:08 PM, Victor Odhner wrote: > I'm trying to bring an unknown monitor up to full resolution. > It's a Visio E241-A1 (TV set), claiming 1920x1080. > I’m running Linux Mint 18.3 Sylvia, with Mate. > The computer (a new desktop) also drives an HDMI cable to a projector, but > that’s turned off right now. > > I used --newmode with xrandr and it seemed to accept that, > but then the --addmode said it didn’t know the new mode: > > xrandr: cannot find mode 1920x1080_60.00 > > Details below. > *So, is there a way to make this work?* > > *The Details:* > > xrandr: cannot find mode 1920x1080_60.00 > > Here's the advice I've been working for: > > https://unix.stackexchange.com/questions/227876/how-to- > set-custom-resolution-using-xrandr-when-the-resolution-is-not-available-i > > Original source: https://gist.github.com/debloper/2793261 > > vodhner@MusicTeam ~ $ xrandr -q > Screen 0: minimum 8 x 8, current 1024 x 768, maximum 32767 x 32767 > DP1 connected 1024x768+0+0 (normal left inverted right x axis y axis) 0mm > x 0mm > 1024x768 60.00* > 800x600 60.32 56.25 > 848x480 60.00 > 640x480 59.94 > HDMI1 disconnected (normal left inverted right x axis y axis) > HDMI2 disconnected (normal left inverted right x axis y axis) > HDMI3 disconnected (normal left inverted right x axis y axis) > VIRTUAL1 disconnected (normal left inverted right x axis y axis > > vodhner@MusicTeam ~ $ gtf 1020 1080 60 > > # 1024x1080 @ 60.00 Hz (GTF) hsync: 67.08 kHz; pclk: 92.30 MHz > Modeline "1024x1080_60.00" 92.30 1024 1088 1200 1376 1080 1081 1084 > 1118 -HSync +Vsync > > vodhner@MusicTeam ~ $ xrandr --newmode "1024x1080_60.00" 92.30 1024 > 1088 1200 1376 1080 1081 1084 1118 -HSync +Vsync > > vodhner@MusicTeam ~ $ xrandr --addmode DP1 "1920x1080_60.00" > xrandr: cannot find mode "1920x1080_60.00" > > vodhner@MusicTeam ~ $ xrandr --output DP1 --mode "1920x1080_60.00" > xrandr: cannot find mode 1920x1080_60.00 > vodhner@MusicTeam ~ $ > > Thanks, > > Victor > ___________ > > > --------------------------------------------------- > PLUG-discuss mailing list - PLUG-discuss@lists.phxlinux.org > To subscribe, unsubscribe, or to change your mail settings: > http://lists.phxlinux.org/mailman/listinfo/plug-discuss >