graphics card - Duplicating a scaled version of one display's output on another in Windows 7

07
2014-07
  • davidjb

    I have a multi-monitor configuration attached to a machine running Windows 7 that consists of:

    • 1 x 24" LCD - connected on DVI; main monitor
    • 1 x ~100" projector - connected separately on DVI on a separate graphics card

    What I'd like to do is have some way of displaying a scaled version of what's on the projector on the main LCD monitor - in a application window - preferably without additional hardware.

    The two monitors are configured as separate displays via Windows without issue, with one being "next" to the other. Physically, the LCD monitor sits at a control desk, whilst the projector is mounted overhead, some distance away. Having something like a scalable window display of the projector output on the control monitor would aid me in positioning content.

    Something like the simple Magnify tool built into Windows is nearly perfect except the shape of the window can't be resized and that it forces you to configure a focal point (cursor, keyboard, etc).

    Is there some form of similar software out there that might handle this?

  • Answers
  • davidjb

    The solution is to use Open Broadcaster Software. The software allows capture from a variety of input sources, including monitor capture, window capture, video capture devices, and more. In this specific instance, monitor capture is the answer and OBS affords various different options to configure capture.

    Now, whilst this software primarily is for the streaming or recording of input sources, it also allows a user to preview the input live. In practical terms, this means being able to monitor input from a display output - exactly what is required. The preview is scaled to the size of the OBS window, and OBS allows for a "projection" of the preview onto a dedicated monitor as well.

    It runs on Windows (32 bit and 64 bit) though OBS Studio is in the works for other platforms.

    As a side note, VLC's DirectShow capture is potentially another option and it does work, but given no specific configuration to capture just one monitor, setting it up is much more difficult.


  • Related Question

    multiple monitors - How can I get Windows 7 to work with two Nvidia graphics cards with different drivers?
  • Max Cantor

    This is similar to this question, but I am using more similar cards with Windows 7.

    I just purchased a Zotac Nvidia GeForce 7200 GS. I have a motherboard with two PCI Express x16 slots. There is already an MSI Nvidia GeForce 8800 GTS being used as the primary card, driving two LCD monitors. I would like the Zotac to output to a TV via DVI-out.

    Unfortunately, when Windows detects the Zotac and installs its drivers, or I manually install them, Windows stops being able to boot up. If I remove them and re-install the MSI 8800 drivers, I can boot again, but Windows can no longer see the Zotac 7200--it shows up as a yellow triangle in Device Manager.

    I've read conflicting reports about this. Some people claim that Windows 7 will support multiple heterogeneous graphics card drivers, as long as they are all using the same driver API ("WDDM?"). Others say that they have to be using the exact same driver, or it won't work. Others claim that you have to use the exact same card. which is it, exactly? I know I can run the MSI 8800 in SLI if I purchase another, but I don't need that kind of power--I just need HD-out to my television.

    I read somewhere that running two cards in SLI precludes you from using 100% of their output ports, so I'm not sure if that's an option. I suppose I could also run two MSI 8800's without SLI, but again, that's more power than I need (and more money than I'd like to spend). Also, I don't think this exact model is even manufactured anymore.

    Any ideas?


  • Related Answers
  • Max Cantor

    The resolution turned out to be as follows:

    1. Shut down.
    2. Remove both cards entirely.
    3. Put the cheap Zotac card in the primary slot.
    4. Boot up.
    5. Let Windows automatically install the Zotac's drivers, which ended up being the same as if you downloaded the latest version from Nvidia's site.
    6. Shut down.
    7. Put the expensive MSI card in the secondary slot.
    8. Boot up.
    9. Let Windows automatically install the MSI's drivers, which ended up being the same as if you downloaded the latest version from Nvidia's site. (The Zotac 7200 and the MSI 8800 both use the exact same drivers.)
    10. Restart.

    I'm not sure how the incorrect drivers got on my PC at all, because both the Nvidia site and Zotac's site provided the exact same drivers. It was probably user error. Ironically, I bet that if I had simply shut down, put the new card in, and booted up again, everything would have been fine. It was probably my blind habit of downloading & installing new drivers from the vendor's site that started the whole fiasco.

    It's a shame, because now, the expensive MSI card is in the half-speed slot on my motherboard, and the cheapo Zotac one is on the primary full-speed slot. But, I'm too nervous about disturbing the tenuous equilibrium I have established to try messing with it. Maybe another day.

  • spapakons

    Well, You could use the fast card on the primary slot and the other card on the secondary slot. I would try uninstalling all nVidia software first, install both cards in that order and boot into Windows. DO NOT let (if possible) Windows automatically install drivers, but instead download and install latest nVidia drivers supporting both cards. Unfortunatelly newest drivers support series 8 and newer, so you have to download the latest drivers for the cheap card that support both. Maybe if you use the latest common driver for both, you can later manually (not running the setup!) upgrade the expensive card from Device Manager. Doing it manually will ensure that only the newer card is affected and the other card is not, and hopefully the expensive card will then have the latest driver which gives better performance, and the cheap card will work as well. In worst case the latest common driver should do well. If everything works OK, try switching the displays from nVidia Control Panel, don't use Windows Display Properties.