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Hi I have two VGA monitors, my GPU is ATI PowerColor 6850 which has two DVI slots, I use adapters for both VGA monitors. If I connect any the two monitors in the first slot it will work right away (along the plugin confirmation sound). And if I connect any of both monitors to the second slot I won't get anything, nor a signal or confirmation sound.

I also tried auto detecting via Catalyst Control Center and Windows Desktop Resolution. I have the latest drivers installed.

EDIT: I found this on the Spec Description:

Display Connectors DL-DVI-I/SL-DVI-D

And in NewEgg:

2 x DVI (1 Single Link, 1 Dual Link)

Could this have anything to do with my issue?

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Thought I am not convinced this is the issue, did you try temporarily unplugging something nonessential (such as a DVD drive) and powering up the second set of pins? – Myrddin Emrys Jun 14 '12 at 22:44
Thanks I will do that right now, will update once I reboot. – Gabriel Jun 14 '12 at 22:49
Nothing changed :( – Gabriel Jun 14 '12 at 22:55
Edit the comment to remove that portion from the issue then (everything after One important thing...) – Myrddin Emrys Jun 14 '12 at 23:08
do you get anything from a voltmeter on the second DVI interface? – MaQleod Jun 15 '12 at 0:53
up vote 2 down vote accepted

Display Connectors DL-DVI-I/SL-DVI-D

THATS your problem

There's three types of DVI connections (well 5, in theory but bear with me).

DVI-D is purely Digital, DVI-A is standard bog standard VGA with a different pin out, and DVI-I is a mix of both. For DVI-I and D you also have single link and dual link, which is irrelevant to the question - it determines maximum resolution.

DVI-I includes analog pins. DVI-D dosen't. As such a passive DVI->VGA adaptor (which is what i mostly see, and is a DVI-A -> VGA converter which you mostly connect to a DVI-I connector) won't work on DVI-D since you're connecting to pins that aren't there

Annoyingly, DVI-D is supposed to have a different pin out just so that you couldn't put a passive adaptor in and find that it dosen't work. The wikipedia article also goes in depth into all this.

In theory you should just use DVI if possible for the second monitor or find an active converter that converts DVI-D to VGA, rather than passes through DVI-A connections to a VGA connector.

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My dell monitor 1908 has one DVI input slot (see this image, I don't have the cable to test it right away. But according to what you explained this cable could be plugged into the second DVI port of my GPU, while the old VGA to DVI could still work in the first slot as it does today. Please confirm on this! – Gabriel Jun 15 '12 at 14:45
yup, thats how it should work. The DVI-D output on the card will work with a DVI cable connected to a DVI input on the monitor. Leave the VGA connection on the output where it works. Amusingly that has a to spec DVI-D connector. – Journeyman Geek Jun 15 '12 at 14:48
Thanks, time to hit the store again. I will update once I have the cable. – Gabriel Jun 15 '12 at 14:58
I found two stores, and they have the same 2 Male DVI-D (Dual Link) Conector ( My video card has only DVI-I (Dual Link) slots and my monitor is DVI-D (Dual Link) (See reference Will it work? – Gabriel Jun 15 '12 at 15:45
Yes. DVI-D cables will go into a DVI-I socket. – Journeyman Geek Jun 15 '12 at 15:48

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