# DVI connection Doesn't Work



## Candres1 (Aug 20, 2007)

I have a GeForce 8800GTS video card that when I hook the card up using the DVI port on the card to the DVI port on my Viewsonic 22" monitor, I get no signal. But when I hook the card up to the VGA port on my monitor (using a DVI to VGA adapter on the video card) I get a signal. I have tried this with my 19" Samsung as well and get the same result...no signal through the DVI, but signal through the VGA. Any thoughts?


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## Sierratango (Sep 9, 2007)

I have the same problem. The dvi port on the monitor receives input throughout the POST, bios and startup screens. Even the first Windows screen (with the copyright microsoft and the horizontal bar) but as soon as the login screen appears, the dvi input ceases. At that point the only way I can get an image is to connect up through the vga adapter.

I previously had the dvi working flawlessly, but recently made the following changes:

- Installed a game (Civ IV: Beyond the Sword) which appeared to alter some Direct X files;
- Installed an analogue tv tuner card (pci - Phillips 7134 chipset) which was never recognised by Vista;
- Removed and uninstalled tv tuner card mentioned above.

I have since tried rolling windows back to several restore points (before any of the above changes were made) but this has had no effect. Also, (before I realised that a signal was coming through vga adapter) I tried using the Vista repair utility on the install CD, but unsurprisingly, it didn't think there was anything wrong.

As I can't find any Vista drivers for my monitor (Acer AL2216W) and because it really sounds more like video card problem to me, I even tried downloading and installing the latest (beta) forceware driver package from nVidia which didn't help at all.

I have no idea what else I can try. I would be grateful for any assistance.


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## Sierratango (Sep 9, 2007)

Ummmm..... nevermind.

It appears that in amongst all the installing and uninstalling, my dvi cable was moved to the other plug on my graphics card. In my folly, I thought it didn't make much difference which plug the monitor cable was plugged into. Obviously I was wrong.

I switched it back and now have no problems whatsoever!


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## zyper95 (Mar 9, 2007)

Have you tried using another DVI cables?


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## Rich-M (May 3, 2006)

There are some monitors where if both plugs are plugged into monitor at same time, even though only 1 is plugged into pc, they won't work. If you just use dvi cable, without anything else plugged into monitor will it work then? Have you looked at plug ends to make sure no pins are bent?


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## Sierratango (Sep 9, 2007)

Ok... The plot thickens...

First of all, if it were a cable or plug problem I would expect that the start up screens and initial microsoft splash screen would not appear. But they do.

I have removed all other plugs and adapters, so that the only link between my monitor and anything other than mains power is the dvi cable.

I have removed all other plugs and adapters from my graphics card.

Having started up my machine, I get as far as the login screen when everything goes black. At this point there are several things I can do to get an image:

- Unplug the monitor from mains power, then reconnect it.
- Unplug the dvi cable from the graphics card, and reconnect it.
- Plug the vga cable (with adapter) into both the graphics card and monitor.

Now, the image that appears once I have done either of the first two things mentioned above is at 800x600. After login this changes to 1024x768. I cannot, through any means, get my monitor to operate at its native 1680x1050 using the dvi cable. It will happily do so using the vga cable, but not the dvi. Even unchecking the "Hide modes that this monitor cannot display" checkbox in the monitor's advanced settings doesn't help. (Display settings -> Advanced settings -> Adapter tab -> List All Modes also reveals nothing above 1024x768).

This is beginning to feel more and more like a resolution problem. As if Vista initially tries to draw the login screen at a higher resolution than the monitor (or graphics card) is willing to allow.

Oh, and further to Rich-M's comment, I previously had the vga cable connected from the monitor to a seperate machine. In the very rare occasions where I had both machines running, I used the monitor's display settings to switch between inputs without problem.

And I'm not sure if this is relevant at all (but I'm beginning to believe that it is), but I have always had a problem with Vista not waking from hibernation. I was never able to get an image on screen after it had started hibernation, so I turned it off in the power management settings. In retrospect, it is possible that the PC woke up, but just never displayed anything on screen, which could be related to my current dilemma.

Thanks for the help so far. I might try running a few more tests...


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## Sierratango (Sep 9, 2007)

Hibernate appears to be unrelated, in so far as none of the remedies mentioned in my previous post fix the display. The PC makes all the appropriate "waking up" noises and signs of activity, but still no image.

Also, the dvi cable works fine if I start up in safe mode.

Could there possibly be something wrong with the cable that would make it work fine at some resolutions, but not others?


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## zyper95 (Mar 9, 2007)

Try lowering the refresh rate of the monitor.


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## Rich-M (May 3, 2006)

That's tough as it could be the video card or the monitor but feels more like video card as I think on it. Can you take the monitor to another pc that has dvi plug, then you would know for sure.


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## blurayz (Sep 18, 2007)

Hey,
this problem has happened to me twice now, the first time with my xfx 8800gts, but that happened straight away and i returned the card as i was thinkin it was a dodgy card, now about 1/2 an hr ago, its happened again, after having my new 8800gts for 3 weeks with no problems, please someone help!!!!


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## blurayz (Sep 18, 2007)

hey haha got it follow this link for explanation ..... http://forums.whirlpool.net.au/forum-replies-archive.cfm/813022.html

but basically unplug your monitor and plug it into another computer and then set the reso up to 1650x1050 then unplug it and plug it back into your computer

it worked for me

good luck


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## simplyflyaway (Oct 4, 2007)

"No Signal" is problem with Acer monitors.

Normal solution is to unplug the monitor and plug it back in, then do not turn it off.

The power button to the monitor is not rigged properly.

I have had no problems since doing this.


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