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Problems with monitors powered off at boot up

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I've got a couple of Samsung 22" LCDs connected to an 8800GTS via DVI's using windows XP SP3. The problem being i like to keep the monitors powered off at the wall but unfortunately when the computer reboots or start it without the screens on the video card just doesn't output anything to them.

 

I have to reset the whole system with the screens on to get any display output. Getting kind of sick of it so do you guys have any idea why the OS or driver isn't starting with display because it can't find a powered on monitor. How can i fix it ?

 

I've dug through the registry and the Nvidia display settings and didn't find anything to always force video output.

 

Thanks Guys

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Your main problem is that the system needs to detect your monitor/s. Try turning your monitors on before you start your system. I think that might be the source of your problem.

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The problem being i like to keep the monitors powered off at the wall

As i said i would prefer it i could keep the monitors off. Surely there is some sort of hack/configuration that tells the OS that i always have the same monitors connected even if they're not on.

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I appreciate your situation. However, take into consideration that, if the system were to detect if something was there or not, it would be when power was on. For example, it would detect a graphics card, if it was there, only if the computer was switched on. Similarly, some USB devices, requires that the device itself is powered before it will detect it (like a mobile phone). Of course some of these USB devices take their power from the port itself.

 

So to answer your question, there is. However, that way back in the day when one had to install device drivers for monitors but that all ended with the introduction of PnP. Like above mentioned USB devices, eg mobile phones and some MP3/Video players, they have to have power in order for the system to detect that its physically there. There isnt a way, at least as far as I know of, for something thats Plug and Play to be detected when its physically got no power at all coming from the mains.

 

Your problem is simple to fix. Just make sure that your monitors have power on when a reboot occurs or when you start the system, then you will never have this problem. I guess a good analogy would be to try to start a car without petrol in the fuel tank.

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I appreciate your help but should be able to be fixed because i've got anothe system sitting on my desk here that boots fine without and monitor (over D-Sub mind you) and when i connect a monitor to it just works. Its just seems to me like a driver OS issue or BIOS issue rather than the fact that its just not possible.

 

As another example what about HTPC's connected to a TV. If you boot one without the TV powered on your telling me you have to reboot the HTPC each time you turn the TV on ?

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The issue is with how the NVidia drivers detect your monitors. They only do it at boot time and not when you connect your monitor to your video card.

 

As mentioned previously if your monitors don't have power then the video card will not be able to report back to the drivers that there is a monitor connected.

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i know this doesn't really apply to you but the catalyst control centre has a detect monitors button however since you need to be able to see to open the control centre and press the button not particularly helpful!

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i know this doesn't really apply to you but the catalyst control centre has a detect monitors button however since you need to be able to see to open the control centre and press the button not particularly helpful!

Thanks. I guess i could always RDP from another machine and then tell it try and detect the monitors. Its still pretty stupid you can't tell the driver to enable the display output even though they aren't any currently connected. This was never a problem using D-Sub but it appears they broke normal functionality with the move to digital (DVI). What the hell are the engineers who design these things thinking.

 

Similar situation but I remember IBM servers would always work if you plugged in PS/2 mice and keyboard after the operating system had booted yet HP servers couldn't. This meant if you wanted to connect a mouse and keyboard after the HP server had rebooted you need to restart the whole system. Freaking stupid.

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I'm having what sounds like a similar problem with my syncmaster Samsung 19in monitor.

 

It occasionally will have problems when starting up, but the most frustrating thing is that if the screen turns off (due to power settings etc) I will not be able to get it to display again until I turn off the PC and monitor from the power point and then restart. Very frustrating!

 

I've tried pressing all buttons on the front of the monitor, and moving keyboard and mouse and get nothing. Sometimes on screen shows - Digital, Analog, Digital, Analog - as if the monitor is not receiving any input.

 

If I make sure the monitor never turns off via power settings - it seems mostly fine, but isn't there an easier solution?? When I tried to play a game the other day and the monitor had to switch it's resolution, same problem - display/monitor turned off and wouldn't turn back on. Power light stays on for 1 sec, but display never returns to the monitor.

 

Internet search suggests - a capacitor problem? or an auto source problem w Samsung monitors... any other suggestions?? am calling samsung helpdesk tomorrow

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Seems if you power on the monitor (system is already running), and then un-plug it and plug it back in to the system (hot-swappable I hope), the system will recognize the new device and the driver will re-send its signal (and get a response from the monitor). Have you tried this already?

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thanks for the ideas. nope no luck with pulling the digital cord out of the back of the video card and re-inserting it.

 

Still to me sounds like a capacitor problem ... only fix is to leave the monitor off for 5-10 minutes and then re-try it. Wouldn't that suggest an emptying of charge of some electrical component? nothing else seems to make sense.

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G'day,

I actually beleive it's more of an HDCP issue which is why it only happens on DVI (& HDMI connections), and not the old analogue D-sub.

What happens is that the source & display devices these days talk to each other and look for a "secret handshake" to make sure all the Copy Protection protocols are in place before they will allow each other to play together (so to speak).

What seems to happen with PC's is that they go to sleep on the job with the handshaking from time to time (if sitting inactive for a short period or input on monitor changed) & a re-sync won't happen unless the whole lot is rebooted.

Check out this device which gets you around these issue's, http://www.gefen.com/kvm/dproduct.jsp?prod_id=4715 . It tricks the Source into thinking that it the display is constantly active. It's also great if you have an older plasma display that isn't HDCP compliant and want to connect a HTPC.

Edited by waynos75

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