Can't get 3rd monitor to work with Eyefinity - it has DisplayPort!

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Mr Davo

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Hi Everyone,

I am attempting to configure EyeFinity with 3 monitors. My graphics card, a PowerColor HD 6850 supports a maximum of 3 monitors, and it sports the following monitor outputs: 2 x DVI, 1 x HDMI & 1 x DisplayPort.

My 3 monitors are all the same brand (Dell) and model (U2212HM UltraSharp), they each sport 1 x DisplayPort, 1 x DVI & 1 x VGA connection.

As all of my monitors support DisplayPort I see no need for a DisplayPort adaptor, and I have connected my monitors as follows:

1). DVI
2). VGA by way of DVI Adaptor (this is necessary because I am using a KVM switch)
3). DisplayPort

Ironically only the 3rd, DisplayPort connected monitor is not working with EyeFinity! I have manually set the connection on the monitor (through the monitor's menu) to DisplayPort. Further when I turn the monitor off and on I see the message: "No DisplayPort Cable" - so the monitor doesn't "believe" that it is connected.

Windows (7 - x64 - Professional) on the other hand responds to the monitor being turned on and off by making the long "doo doo" sound that it typically makes whenever a USB connection is established! However this being said "Screen Resolution" Control Panel item only ever reports that two monitors are connected!

Furthermore ATI Catalyst can only see two monitors connected - it sees one Analog (due to the adaptor) and one digital (as pictured below).



Any help with getting my 3rd monitor working will be greatly appreciated. I have considered uninstally & reinstalling the driver - but I am not convinced that this will help as the monitor is reporting "No DisplayPort Cable"!

Thanks

Davo

 

inzone

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Just for the sake of trouble shooting and testing the displayport cable , have you tried connecting just one monitor and using the displayport cable to do that?
Then if that works add the DVI cable to the second monitor and then the vga to the third monitor just to see what happens and if the vga ends up being not recognized.
 

jdenova007

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"To enable support for more than 2 monitors, “active” DisplayPort™ adapters/dongles are required (or monitors with direct DisplayPort™ connectivity must be used)."

From here - http://support.amd.com/us/eyefinity/Pages/eyefinity-dongles.aspx

So he doesn't need an active adapter because his monitor has a native DP connection..... I am not sure why it can't see it though....

Can you try DVI and DP... without using the other dvi... ?
 

kitsunestarwind

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Try the configuration without using a VGA connection, I get the feeling Eyefinity is meant to work only for all digital outputs (displayport/dvi/hdmi)
And if your monitor is directly linked via displayport you won't need any kind of active adapter
 

Mr Davo

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Hi,

I have tried without the VGA connection, and the monitor still reports "No DisplayPort Cable" even though I here a "doo doo" noise from the computer - indicating that the computer recognizes that a connection is being established whenever I turn the monitor on / off.

At this point I am beginning to suspect that my 2 meter long DisplayPort cable is simply too long for the Dell U2212HM monitor, and due to this I am considering investing in either a shorter DisplayPort cable or an active DisplayPort to DVI adaptor. It feels like a bit of a pitty that I may need to resort to an adaptor even though my monitors natively support DisplayPort, however I figure that an active adaptor is likely to boost the signal and therefor give me greater cable length.

Any other input at this point is very welcome.

Cheers

Davo

P.S.: I have also uninstalled / re-installed the Catalyst Control Centre and Drivers - but this didn't lead to any improvement.
 

Mr Davo

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I CAN'T BELIEVE IT - I DIDN'T HAVE THE CABLE PUSHED ALL THE WAY IN!!!

IF YOU HAVE A DELL U2212HM THE CABLE IS HARD TO GET ALL THE WAY IN! YOU REALLY NEED TO APPLY QUITE A BIT OF FORCE.

Hopefully this post helps somebody in the same position as I was on - thanks again to everyone who kindly offered suggestions :)
 
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