Monitor Setup Help Please

Discussion in 'Hardware' started by RhinoTrader, Dec 4, 2007.

  1. Hi guys - I know there are one or two computer experts out there so...

    I have just had to do a complete re-install of windows XP pro on one of my home machines after a virus took down my system beyond repair. I had not got a full image backup so I have been through the process of downloading all my drivers etc and all is now just about fine with the exception of my dual monitor display.

    My graphics card is a NVidia 7900 GTX 512mb to which I have 2 ViewSonic 20" displays hooked up. However, windows only recognises one display. Both monitors work independantly (ie plug either DVI into the first socket in the computer and it displays) but not together (i.e. I cannot set-up multiple displays). This dual monitor setup was working before my resinstall.

    Nothing in my limited knowledge works. There is no option in the display settings to add a 2nd montior (despite it being plugged in) and the NVidia control panel only shows one monitor also. Lastly, only one monitor shows in device manager.

    I should mention that I have installed the drivers for the monitor(s).

    Any thoughts/solutions most welcome
    Thanks
    Mike
     
  2. gnome

    gnome

    I'm presuming you went in Display/Settings and checked "Extend this monitor to Desktop". If not, try that.

    You might also try uninstalling the Nvidia driver. XP has a library driver which will likely run the monitors at full function minus a bell or whistle.
     
  3. thanks gnome

    yes - i had indeed tried the "extend windows over 2nd monitor" - or at least I would have except for the fact that it does not present me with the option.

    I may try uninstalling the NVidia driver, altho I couldn't use the 2nd monitor before installing it in the first place (i.e. when windows was first reinstalled).

    It is as if the monitor did not exist, except that I can see it with my own eyes. :)

    i'm starting to wonder whether there is a hardware fault with the 2nd socket on the graphics card.....??

    i'm waiting form a call-back from the computer manufacturer technical support desk in india right now. hopefully they can shed some light on it but I have my doubts...
     
  4. gnome

    gnome

    You might try plugging each monitor into each DVI port to verify that each port works.

    Try plugging in both monitors, and though one doesn't light, install the driver with both plugged in. Then try to "Extend to Desktop".
     
  5. gnome

    gnome

    Assuming both monitors light separately on each DVI port, then the possibilities are:\

    1. The video card has lost its ability to display both monitors at once.

    2. Something about the driver is not allowing extended desktop.

    3. You managed to foul Windows Desktop function with your reinstall. You said you just did a fresh install, but if I were troubleshooting, I'd do it again... then after installing the chipset driver and before any other drivers or software, I'd try Extending to Desktop. If it still doesn't work, then it's likely the card.

    Hopefully you have an additional hard drive for this.

    Good luck,
     
  6. gnome - thanks very much for your help. i have finally solved the mystery - here's what was going on in case anyone experiences something similar....

    whilst my desktop was out of action (virus) i had borrowed one of the monitors to use with another machine (laptop). it was this monitor which no-longer worked on the machine in question. i couldn't see that this would be the reason as i had done this before problem free. to check, i ported it back to the laptop but it didn't work. i then ported the other monitor to the laptop to double check - it did work with the laptop. BUT, low-and-behold, when ported back to the main desktop it wasn't recognised. nor was it recognised with the laptop when i tried it again. i was left with a "zero-monitor" setup. ahem.

    to cut a long story short, the laptop was triggering something inside the monitor, flipping some electric switch somewhere. the solution was to totally unplug the monitors from the power socket and leave for 20 secs or so to allow them to reset. Now they work fine. Seems so simple in hindsight. never seen anything like that before.

    cheers
     
  7. Bizarre problem. What is the model of the monitor and the laptop? I have never seen that happen before and I go through a lot of machines.
     
  8. JackR

    JackR

    Pure guess - but I'd say it is a monitor "feature" to lockout\prevent simultaneous analog and DVI inputs. Once set it cannot change until powered down.
     
  9. Monitors are Viewsonic VX2025wm LCD widescreens. Decent kit. Laptop is a dual core Asus - won't bore you with the spec but it's not bad.

    I was really concerned and very confused - I am no comp novice but I have never seen anything like this before either and to have two monitors blank out on you is un-nerving.

    The problem was not related to dual use of VGA and DVI inputs. When I switched from desktop to laptop I actually took the DVI cable out of the desktop and used it to connect to the laptop. Additionally, I've used these monitors previously to hook up to 2 machines simultaneously.

    I was always (semi) confident that the monitors would work again as nothing ever went "pop" or "fizz". I just couldn't get a picture. In the end, the crudest solution was the best - pull out the power cable and wait.
     
  10. g

    to cut a long story short, the laptop was triggering something inside the monitor, flipping some electric switch somewhere. the solution was to totally unplug the monitors from the power socket and leave for 20 secs or so to allow them to reset. Now they work fine. Seems so simple in hindsight. never seen anything like that before.

    cheers
    [/QUOTE]

    Having had a similar experience connecting 4 monitors I thought I would jump in and give you my 2 cents. Before installing new video drivers or software, its always best to completely uninstall all traces of the old software and drivers, even the old directories and old register entries, I use CCleaner to erase old entries. Then check you have the correct drivers for your monitors, you can check if windows recognizes the monitor type by looking in system and looking under hardware, monitors and you can see how many monitors are connected and the type they are. You can then install the latest video card software from the manufacturers website, do not use the CD as the software distributed is generally out of date.
     
    #10     Dec 5, 2007