No feed to primary monitor when secondary monitor is off.

My computer desk sits next to my entertainment system, and I have it connected to two monitors: the primary 22” Viewsonic LCD (DVI) and my 42” Toshiba TV (HDMI hooked in via my receiver). When I just want to browse the ‘net or email, I use the primary monitor. For gaming and movies, I use the TV. For a couple of years now, I’ve had display options to always display the TV (monitor 1). If the TV was off, it would default to the Viewsonic, per the Windows feature to always default to the current monitor if only one was on. If the TV was on, it would stop feeding the Viewsonic and default to the TV, so that any games or movies would display on the TV and not cause any issues fullscreen. This way the TV being on or off determined whether the PC would feed to it or not, and I’d only turn on the power hungry TV for entertainment.

About a month ago, my monitors started behaving oddly. The PC would power up normally and load Windows to the Viewsonic, and during the load up screen the Viewsonic would power down. The only way to see the screen was to turn on the TV. This is on Windows 7 64 bit Home Premium (up to date).
Things I’ve tried:

• Set the Viewsonic to be the primary monitor and settings to only display on the Viewsonic. Result: If the TV is off, there’s no video to the Viewsonic. If the TV is on, it is black (as expected since I've set the monitor to receive the feed) and the feed goes to the Viewsonic.
• Set the monitors to extend across both the Viewsonic and TV. Result: If the TV is off, there’s no video to the Viewsonic (it goes into powersaving mode). If the TV is on, the display correctly extends across both the TV and the monitor.
• I uninstalled and reinstalled the NVidia graphics driver, currently using WHQL 337.91. Result: If the TV is off, there’s no video to the Viewsonic.
• On boot up F8 into the Advanced Boot Options and choose option “Enable low-resolution video (640x480).” Result: computer correctly defaults to the Viewsonic if the TV is off. Since this is loading up with a basic VGA driver, it suggests an issue with the advanced NVidia driver or with the dual monitor support?
• Unplug the HDMI cable from the graphics card to the TV then boot up. Result: computer correctly defaults to the Viewsonic if the TV is unplugged. Of course constantly unplugging the HDMI cable is a hassle and will eventually result in the plug breaking.
• Unplug the electricity to the TV and receiver from the wall socket and boot up. Result: If the TV is off, there’s no video to the Viewsonic. This is the most interesting one, as I wouldn’t have expected it to recognize that TV with the power cable unplugged.

I’ve seen lots of forum posts by people that want to disable monitor switching, but I like it and want it fixed. It works for my setup. I couldn’t find anyone online after a couple of hours of searching with my problem.
My hardware:
- Motherboard: ASUS Intel Z77 ATX DDR3 2400 LGA 1155 Motherboard P8Z77-V
- Proc: Intel Core i5 3570K Processor 3.4 GHz
- Soundcard: Sound Blaster X-Fi
- Graphics card: GIGABYTE NVidia GeForce GTX 670 2GB
- RAM: Corsair Vengeance 8 GB ( 2 x 4 GB ) DDR3 1866 MHz (PC3 15000) 240-Pin DDR3 SDRAM
- SSD: Samsung 830 - Series MZ-7PC064D/AM 64 GB 2.5 Inch SATA III MLC Internal SSD
- Primary boot HDD: Seagate Barracuda 7200.12 SATA 1TB ST31000528AS
- Secondary HHD: Hitachi Deskstar SATA 750GB HDS721075KLA330
- Lite On DVD-RW
- PC Monitor: Viewsonic 22” 1620x1050
- TV: Toshiba 42” 1920x1080

Thanks in advance.

I figured out what was going on. On the Screen Resolution dialog box, your monitors are represented as two rectangles at the top. My rectangles originally had my monitor on the left and TV on the right, but physically the TV was on the left. So when I would extend, dragging the cursor off the right side of the monitor, would have it appear all the way on the left side of the TV (also on the left) which was a bit odd. One day I saw a Windows tip that you could just drag the monitors into whichever configuration you wanted, and so I dragged them to match their physical set up. It must have been around then that the issue started.

I was playing around with Windows P today and noticed that Windows kept saying that my TV was my primary monitor and the Viewsonic was the "Projector." That's when I realized that Windows prefers the primary monitor on the left on secondary on the right. When I dragged them back so that the TV was on the right in Screen Resolution and rebooted, the problem was gone.

I have found a solution.
My setup is an PC with an ATI radeon HD7700 connected to a PC-monitor (primary) through HDMI and a AV receiver through displayport/hdmi-adapter, which in turn is connected to an LCD TV (secondary).

If both screens were plugged in, both had to be ON to get feed to both. Turning the secondary screen off would cut the feed to the primary monitor. I would have to physically disconnect the secondary screen to get any feed back to the primary monitor.

It seems windows has different "default settings" assumed for the different monitors it detects. I.e, having 1 or 2 monitors physically connected correspond to two different sets of settings, and the receiver can act as a third device by itself, triggering yet another set of settings. The problem, it seems, comes from the fact that the AV receiver can report as a connected HDMI device, even if the TV it's connected to is off, or the receiver itself is off. This is the desired behavior, on the receivers part, because you may want to output sound to it even though the connected TV is off.

My solution: Connect both monitors, turn off the second monitor to trigger the weird behaviour which cuts the primary monitor as well. Now there is no way to see the windows desktop directly. Use some remote desktop tool from another PC (RDP/Teamviewer/VNC, i used Teamviewer) to access the windows desktop . You'll probably find that the default setting is to send the audio/video feed to the secondary monitor, even though it is turned off. . Just change the settings into whatever is appropiate. This will now become the default setting upon detecting that specific state.

kameboy said:

I have found a solution.
My setup is an PC with an ATI radeon HD7700 connected to a PC-monitor (primary) through HDMI and a AV receiver through displayport/hdmi-adapter, which in turn is connected to an LCD TV (secondary).

If both screens were plugged in, both had to be ON to get feed to both. Turning the secondary screen off would cut the feed to the primary monitor. I would have to physically disconnect the secondary screen to get any feed back to the primary monitor.

It seems windows has different "default settings" assumed for the different monitors it detects. I.e, having 1 or 2 monitors physically connected correspond to two different sets of settings, and the receiver can act as a third device by itself, triggering yet another set of settings. The problem, it seems, comes from the fact that the AV receiver can report as a connected HDMI device, even if the TV it's connected to is off, or the receiver itself is off. This is the desired behavior, on the receivers part, because you may want to output sound to it even though the connected TV is off.

My solution: Connect both monitors, turn off the second monitor to trigger the weird behaviour which cuts the primary monitor as well. Now there is no way to see the windows desktop directly. Use some remote desktop tool from another PC (RDP/Teamviewer/VNC, i used Teamviewer) to access the windows desktop . You'll probably find that the default setting is to send the audio/video feed to the secondary monitor, even though it is turned off. . Just change the settings into whatever is appropiate. This will now become the default setting upon detecting that specific state.

You're brilliant. I tried what you said through RealVNC, and I found that by some cosmic coincidence the monitor was set to the secondary even after it was turned off.

I have registered solely to say thanks to kameboy for that brilliant solution. I just spent the entire day trying to find a solution to my problem, which was pretty much the same as yours. My computer is connected to an AV receiver by HDMI and an ordinary monitor by VGA. Whenever I turn the receiver off, the monitor goes to sleep.

I thought I'd tried just about everything, but your suggestion is the only thing that has worked. THANK YOU!!!!!