Dell OptiPlex 990 SFF, Dell UltraSharp U2312HM = Video flickering over DisplayPort

Is this 990 using the onboard DP or a discrete video card DP?

For troubleshooting on this specific 990, can the user connect a single U2312HM via DP to DP cable, set the resolution to 1920x1080 and tell us the results?

Hi Chris,

I'm also wondering if this could be a driver issue.  I have deployed a driver for the older version of this monitor, the U2311H so that it went to sleep properly on connected systems.  However, I can find no driver whatsoever for the U2312HM.  Could lack of a driver be affecting things?  Is there a driver for the U2312HM - when I search on Dell's driver page, it returns "No downloads are available for the [ Dell U2312HM Monitor ]."

Hi Chris,

The Dell OptiPlex 990s are using the Intel onboard graphics, so there is one DisplayPort and one VGA port on each system.

Good point about the resolution - I will make sure that gets checked and report back.

Regards,

Hi Chris,

I had someone in the office try the DisplayPort connection again overnight, and they made sure the resolution was set to 1920x1080.  It still flickers.

- I'm couriering additional DisplayPort cables today (StarTech brand; the one in use now isn't a Dell supported brand) so they will have those to try sometime next week.

- I'm going to try get a short video clip of the flickering so that we can see exactly what the behaviour is.

There are no Windows 7 drivers. Windows 7 will load its generic PNP driver for the monitor. The only U2312HM drivers are for Vista 64.

Vista 64 driver http://dell.to/wqAEno

Vista 64 PowerNap Application http://dell.to/yhS5wK

I am experiencing a similar issue with several of our Optiplex 990's using the built-in Video Card where the appication windows flicker and moving between dual monitors the windows either ghost or disappear altogether.  The user can then reboot and the machine will work correctly for a day or so and then will begin the same behavior.  We are using the DP Cables provided by Dell for the one monitor and a Dell vga cable for the other monitor.  Any thoughts would be much appreciated.

Thank you,

Hi Chris,

I'm going to get DisplayPort to DisplayPort tried on one or two different Dell monitors that we have at this office to see what happens.  I'll post back in a few days once I get that done.

Hi Chris,

I have sent new Startech cables and had them tried with the OP 990 and U2312M.  The flickering still occurs when using DisplayPort to DisplayPort, but it doesn't occur when using DisplayPort to DVI.  This leads me to believe that the output from the PC might be okay, and rather it's the DisplayPort input on the monitor that's bad.  What do you think?

I have posted a video of the flickering here (the link will expire on March 18, 2012): https://rcpt.yousendit.com/1402977728/0aa9f8d9a70bac9605297d7d19a97cef

I have never heard of a DP port going bad but it's possible.

I forgot to say I the screen starts to flicker if I get a call on my cell phone. Does not happen when its connected using DVI.

Hi

I have 3 Dell U2312HM monitors used on my computer. When I connect all monitors using DP cable to DP port (have 10 of those) I get flickering on ALL monitors. It does not always happen but when it does and it is very annoying when one of the screen starts flickering.

Only way to fix this is either connect ALL screens using DVI (I have 4 of those ports) or restart the display adapter by either starting a game and let it switch over to 3D mode, go into catalyst control panel and switch CF on and off, or when I restart the computer.

I have dual Asus Radeon HD 6970  Directcu ii

Since other people seem to have no problem using my graphics card display port on other monitors but a lot of people is having flickering when using the dp ports on this monitor series, it has made me believe this series has faulty display ports or at least a batch of monitors having this problem.

Hi Chris,

I have just taken delivery of 6 x Dell UltraSharp U2412M at my head office.  I connected two of them to a Dell Vostro 230s desktop with VGA and DVI, and they work fantastic.  I connected a second set of two with Startech 6' DisplayPort to DisplayPort cables to my Lenovo docking station.  They flicker exactly like the video that I posted earlier from my other office!  To eliminate a driver issue as the cause, I booted to the BIOS and the monitor displaying that still flickers!

So far I have 3 x U2312HM and 6 x U2412HM, and I have another 3 x U2312HM on order right now.  These have not been purchased all at once, they are several months apart.  The U2312HM's are in my office overseas, and the U2412M's are in my office in Canada.  I think I have done everything I can to isolate this problem to the DisplayPort input of these monitors:

- I tried multiple cables from multiple manufacturers (Cables To Go and StarTech)

- I tried multiple output devices (Dell OptiPlex 990 and Lenovo dock)

- In case it was just the 'Auto' input detection, I have forced the input to DisplayPort.

To work around this issue, I've spent a good amount of money on DisplayPort cables, only to have to buy DisplayPort to DVI cables for the devices that don't have DVI output.  Since those are the most expensive cables, I'm in for roughly triple the cabling costs I had been expecting on all these monitors!

What should I do now?  Do I call support or is identifying this on here adequate?  Obviously the monitors are covered by Express Exchange warranty, which I could claim through support, but I don't want to start doing that if the replacements are going to exhibit the same behaviour!

One further update to this: things are not as bad as I thought.

After coming back to the office the next day after setting up my 2 x U2412M's with DisplayPort from a Lenovo dock, there is no flickering.  I did set each monitor to be forced to the DisplayPort input, but I've now used the monitors for two days and there hasn't been any flickering.

So my problem is still isolated to the OptiPlex 990 & UltraSharp U2312HM.  I have more OP 990s on the way, as well as more U2312HMs, so I'll update in a few weeks once I have those deployed.

Im having the same issues on a u2412m. mini dp > dp and i get a lot of occasional flickers but when i run fullscreen programs or wake it from sleep the screen goes on/off like crazy and can stay off for 1-2 sec at a time =( This goes away from time to time but it doesnt happen when the monitor is connected over dvi.

Problem is im using 3 screens and don't have dvi-ports to spare. My 7950 holds 2xMiniDP, 1xHDMI and 1xDVI. Anyone has any idea on how to solve this? The flickering is driving me insane...

win7

dell u2412m

amd hd7950 (reference card; no OC, no mods)

i7 2600k

You were right veechee2! Ive tried with 3 different brands of miniDP>DP and finally bought a miniDP>DVI cable. The cost was about the same (4SEK = ~0.3USD more :P) and now I can run all screens!

Is this a common problem on the DELL U2412M? I've never heard or read anything about it before.