Thank you all for the help so far, I think I'm stuck trying to edit or create a proper xorg.conf file that will give me a consistent display on start up.

I have two identical monitors - Samsung S20D300, Ubuntu 14.04, 4GB RAM, Intel E5300@ 2.60GHz, Nvidia GeForce 8400 GS w/ VGA and DVI-D outputs - 1 monitor connected to each

In Nvidia XServer settings utility, one monitor shows as "Samsung S20D300(CRT-1)" (connected to VGA) the other as "CRT-0" (connected to DVI-D w/ proper VGA to DVI-"D" adapter) Same setup worked fine in Win8.1.

Settings and resolution on the Samsung, are fine, 1366x768, the "CRT-0" is only showing at 1360x768, with lower options available. The 1360 monitor is to the right of the 1366 (main) monitor and the left edge of the 1360 is not visible w/ a black bar on the right side.

I have tried the X.Org Nouveau driver, same thing, using the onboard card + the Nvidia is also out. Installed various legacy and current Nvidia drivers, same.

Using xrandr I was able to force the screen to the right into 1366 and correct position but this of course did not survive reboot. I think I can edit the xorg.conf file but I cannot find exactly how to do that.

Any - all direction, help, questions and suggestions will be very, very much appreciated. Thank you!

  1. Double check that they are actually identical. Look at the product ID and dates and similar things. I had a case at work where two monitors we thought were identical didn't support identical sets of resolutions, and I discovered that they weren't identical. One was a slightly modified version released a couple months later. They had the same model number and had been sold as if they were the same product, but were not.

  2. Get your hands on an actual DVI cable. Sometimes adapters do funny things. You say it's a "proper adapter." I have no idea what that means (what's an improper adapter?). I do know that I've used adapters which were supposed to convert one cable to another type and did not, whereas the system worked fine with the correct cable. DVI cables shouldn't be expensive. Where I live, you can often find them being thrown away by people moving to HDMI and DP, although that may not be relevant to you.

  3. Try switching the ports the two monitors are plugged into. Presumably, you expect the problem to occur on whichever monitor is plugged into the DVI, but maybe that monitor is broken or something.

  • Thanks for the ideas - both monitors were purchased the same day from the same store, they functioned as identical monitors in Win8.1 but however slight the chance, it is worth checking if they really are identical. The only monitor input is VGA so will a full cable act as more than an adapter? Again, still worth a shot, will do. The current adapter also worked in the Win8.1 set up. We did switch the ports - it's the port not the monitor. Thanks again, good all. – Hockeybik Jul 10 '15 at 23:41
  • My mistake. I assumed the monitor had vga and dvi inputs, and you just didn't have a dvi cable so you substituted a vga cable and adapter. In this case, It's much less likely that the adapter is the culprit. It's not impossible though. Sometimes windows has proprietary workarounds for bad, non-standards-conforming hardware. But it's much more likely that the problem is elsewhere. – user3113723 Jul 10 '15 at 23:51

It's possible that something (the adapter? the use of dvi?) is preventing X from discovering the properties of your monitor, which is why it isn't showing up by name.

Something you could try:

  1. Get xrandr.

  2. Run xrandr to dump out your monitor settings. Presumably, the two will show up differently. (If not, the problem is elsewhere, and easy to fix.)

  3. Read through all of the horribly complicated documentation relating to adding custom modelines for displays. There are some references in man xrandr, although you'll probably have to do a bit of googling to.

  4. For the undiscovered monitor, add a custom modeline identical to the modeline you're using for the good monitor (normally this could be dangerous because if you tell the monitor to refresh faster than it actually can, it could break parts of it, but that shouldn't be possible here).

  5. Try to start the monitor with the higher resolution you want using xrandr (you'll have to read more docs, obviously). If this works, you'll in principle be able to make both monitors work how you like using a more convenient interface (i'd say try arandr); this is just diagnostic.

  • Do I understand that I cannot make the changes I need using ARandR? I have to do that in xrandr via CL? I'm not uncomfortable w/ CL, just not that experienced. Thanks. – Hockeybik Jul 11 '15 at 1:10
  • I don't know. You may be able to use arandr. I've never tried. I know you can do it with xrandr, so I mentioned that. – user3113723 Jul 11 '15 at 1:16
  • OK, got xrandr to force the new resolution and it worked, and with the Xorg driver too - but I could not figure out how make it permanent. Must be a solution... hummm... – Hockeybik Jul 11 '15 at 6:29

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