Displayport problem, vid card or monitor?

[Spike]

First the relevant specs:

6970
3 x Dell U2412M using 2 x DVI 1 x Mini displayport->reg displayport cable
5760x1200

I turn on my pc tonight and my lcd connected with the displayport won't get a single, it goes into powersave mode and I get some sort of error regarding the displayport, something along the lines of "The system has detected a problem with the connection between your computer and the DisplayPort display that will prevent you from using the highest resolutions and/or refresh rates."

Any ideas? The LCD appears to work with a DVI connection but won't work even if I swap around the display ports connections on my vid card.

EDIT. Appears to be the LCD. I swapped positions with one of the other lcd's and the setup is back to normal. Could the cable have cause an issue with the lcd or could it have been just a bad monitor?

 

[JSt0rm]

You need a powered mini display port cable or else the card will only see 2 displays. New egg has them.

 

[CVSiN]

You need a powered mini display port cable or else the card will only see 2 displays. New egg has them.

he has a NATIVE DP monitor..
he does NOT need an active adapter..
no idea what is causing that sounds like a bad port. I would contact Dell on an RMA for it..

 

[SpicyTime]

Same thing happened to me. I also have three Dell U2412Ms, using 2 DVI ports and one DP. Half the time, the DP monitor would not detect the DP connection, and all other times it would not detect the right resolution. It was incredibly frustrating, and I could not find any answers after googling for hours.

The next day, I booted up my computer and everything worked perfectly. I haven't had this problem for about a month. My guess is it could be related to Windows auto-installing DP drivers for the U2412M, and requiring multiple reboots. Try that, and hopefully you'll end up as lucky as I did.

 

[Spike]

Same thing happened to me. I also have three Dell U2412Ms, using 2 DVI ports and one DP. Half the time, the DP monitor would not detect the DP connection, and all other times it would not detect the right resolution. It was incredibly frustrating, and I could not find any answers after googling for hours.

The next day, I booted up my computer and everything worked perfectly. I haven't had this problem for about a month. My guess is it could be related to Windows auto-installing DP drivers for the U2412M, and requiring multiple reboots. Try that, and hopefully you'll end up as lucky as I did.

Interesting, you could be correct. Right now things are working great since I swapped monitors but who knows how long that will last? I'll give it a try again with the one that had issues and see if the DP magically fixed itself or is still busted. If it's still busted I'll take advantage of that nifty advanced RMA these babies come with.

 

[iCyborg]

Can you try setting 640x480 mode over DP with that problematic lcd?
It sounds like it's a monitor issue during DP 'handshake' process. DP has 4 links that can each go at 1.6gbps or 2.7gbps (and 5.4 in DP1.2). When you connect lcd, GPU will send some test signals to determine the max speed it can drive the links. I believe if these are not 4x2.7, you'll receive that message even if the mode you're using can be supported. It seems like GPU didn't receive anything during this process, because 1 link at 1.6gbps is enough for 640x480, so it should be able to at least use that instead of going to powersave mode.
It's a fairly new monitor, and sometimes firmware updates or display driver workarounds for specific panels are needed, so it could be that a SW fix could resolve the problem. Seeing that 2 of you have the same problem, it might not be an uncommon problem.

 

[Spike]

Odd, I had a blue screen and when I restarted this problem happened again with the LCD connected using displayport, the one I switched with another one last time. So now with 2 having the same problem I decided to swap them back, connecting the displayport cable to the one that had the issue last time and going with DVI on the current problem lcd and you know what? They worked again! Why would I be getting this problem again, but with a different LCD? I don't recall a blue screen preceding this problem last time but who knows, I do seem to get them once a month these days which is somewhat annoying.

I tried to force the problem lcd into 640x480 with catalyst but it remained off though I could not be sure this actually worked as windows would not let me go below 800x600 and catalyst had issues selecting the third LCD. Now I'm not sure about putting in an RMA request with Dell since the same problem may occur again. I wonder if it's the monitors, GPU, drivers, or some mix of the 3? Could a bad displayport cable cause this? I only have one I bought from monoprice, maybe it's time to order another?

 

[NoQuarter]

Odd, I had a blue screen and when I restarted this problem happened again with the LCD connected using displayport, the one I switched with another one last time. So now with 2 having the same problem I decided to swap them back, connecting the displayport cable to the one that had the issue last time and going with DVI on the current problem lcd and you know what? They worked again! Why would I be getting this problem again, but with a different LCD? I don't recall a blue screen preceding this problem last time but who knows, I do seem to get them once a month these days which is somewhat annoying.

I tried to force the problem lcd into 640x480 with catalyst but it remained off though I could not be sure this actually worked as windows would not let me go below 800x600 and catalyst had issues selecting the third LCD. Now I'm not sure about putting in an RMA request with Dell since the same problem may occur again. I wonder if it's the monitors, GPU, drivers, or some mix of the 3? Could a bad displayport cable cause this? I only have one I bought from monoprice, maybe it's time to order another?

I had a DisplayPort cable from monoprice that I had issues with, did some reading and found that Monoprice DP cables were missing one of the extra ground pins and had strange issues. This was a year or 2 ago though so idk if they ever fixed the cables. I got a different cable and everything worked perfect after.

 

[Spike]

I had a DisplayPort cable from monoprice that I had issues with, did some reading and found that Monoprice DP cables were missing one of the extra ground pins and had strange issues. This was a year or 2 ago though so idk if they ever fixed the cables. I got a different cable and everything worked perfect after.

interesting... maybe I need to go get myself a displayport cable from elsewhere. Thanks for the insight.