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Discussion in 'Mac Pro' started by Garamond, Oct 9, 2010.

  1. Garamond macrumors regular

    Joined:
    Oct 17, 2004
    #1
    Am I doing something wrong here? When I hook up my extra 20" Apple Display (with adapter) it's not recognized by the system at all. Only my main display.

    Specs in signature.

    Any ideas?
     
  2. dissolve macrumors 6502a

    Joined:
    Aug 23, 2009
    #2
    Both are DVI, correct? So you're using a DVI -> MDP for the 20 inch monitor? Have you tried plugging the 20" directly into DVI to be sure it's working properly? If that checks out, it may be the adapter. Some cheap ones haven't been working out for users on here. You shouldn't need a dual-link adapter unless you are trying to use 2 DVI displays and a MDP display.
     
  3. Garamond thread starter macrumors regular

    Joined:
    Oct 17, 2004
    #3
    The 5870-card has two DVI's and one MDP, and I'm using Apples own adapter (I have two of them, tried both). Only by connecting to the one MDP slot, the monitor gets recognized.

    :confused:
     
  4. dissolve macrumors 6502a

    Joined:
    Aug 23, 2009
    #4
    Just so I'm clear, have you confirmed that each monitor works on all three ports independently? Then, no matter which port you plug in the second monitor, it's not recognized? Make sure you are working within these limits:

    http://support.apple.com/kb/HT4279
     
  5. yuccaview macrumors newbie

    Joined:
    Jun 22, 2010
    #5
    I had the same problem and Apple thought the 5870 was defective and sent a replacement but as a last resort I removed the card and reinstalled it. Both monitors came up and have ran perfect since. I think the way these
    cards are installed that in shipment they loose a connection. What ever the
    case we refused shipment on the replacement card and I have had zero issues. My machine is the 6 core with 16 gig of ram and an old 30 inch and new 24 inch Apple screens. Very happy with this machine.
    Don
     
  6. telequest macrumors regular

    Joined:
    Feb 1, 2010
    Location:
    NJ
    #6
    On my new 2010 hex, the 5870 has ONE DVI port and TWO MDPs. Doesn't yours?

    I'm having similar trouble, except that the DVI port works, but not the MDPs. Just got 2 new Dell U2410s. They each work individually when hooked to the (one) DVI port on the 5870.

    They also each work when I connect them to my 2009 MacBook Pro's MDP port via a NewerTechnology MDP to DVI adaptor.

    But neither monitor works connected to the Mac Pro via the same adaptor to either MDP connector on the 5870 ... not as a single monitor, and not as a second monitor (my goal, of course, is to run both U2410s side by side, one connected to the DVI, and the other connected to one of the MDPs via adaptor).

    So it seems that both MDPs on my 5870 are completely dead, whether or not another display is connected to the DVI port.

    Before I call AppleCare, any advice on anything else I should test? I'd consider getting another MDP-to-DVI adaptor, but if the one I have works connecting the monitors to my MBP, I can't figure how that could be the problem.

    Thanks as always.
     
  7. b.lam macrumors newbie

    Joined:
    Sep 5, 2010
    #7
    Try the following: with the MDP plugged in, try to gently push the plug horizontally to the right or left. My MDP only worked when being pushed a little bit to the right. However, the slightest touch afterwards and it would loose the connection again. I use the DVI now without any problems (even the snowy-screen effect seems to be gone).
     
  8. telequest macrumors regular

    Joined:
    Feb 1, 2010
    Location:
    NJ
    #8
    It seems that something along these lines was affecting my setup too.
    - As a next step, I tried my Apple MDP-to-VGA adaptor ... and my second Dell U2410 suddenly worked! (with the other attached to the 5870's DVI port).
    - So I decided to try the second monitor via the NewerTechnology MDP-to-DVI adaptor once again, and this time it worked (it didn't before). I guess it was just a matter of wiggling to make a good contact. So far it seems to be a stable connection.

    So now I've got my setup: two Dell U2410s running off the 5870, one via the DVI port, the other via a MDP using MDP-to-DVI adaptor.

    Now I've got to figure out how to calibrate these things so they match ... is it possible that the optimal setting for each is affected by whether it's running via the 5870's DVI vs. MDP-to-DVI adaptor?
     
  9. telequest macrumors regular

    Joined:
    Feb 1, 2010
    Location:
    NJ
    #9
    MDP not ready for prime time?

    Given the experience b.lam and I had with iffy connection via MDP, is it possible that MDP isn't exactly up to Pro standards? Seems pretty unreliable if wiggling a connection that otherwise seems firmly seated is needed to make it work. I seem luckier than b.lam since mine seems to have wiggled its way to an OK connection – at least for now.

    I'd be happier if my 5870 actually had 2 nice big solid DVI ports and 1 teeny little MDP, just like the OP seems to have on his/her 5870.

    Garamond, do you really have 2 DVI ports on your 5870? Is that some kind of non-Apple variant? I'll trade you one of my MDPs for one of your DVIs :D
     
  10. b.lam macrumors newbie

    Joined:
    Sep 5, 2010
    #10
    These were exactly my thoughts too.

    They could also have used two normal DP ports. The space is there and the normal DP feels more reliable to me. Trying to squeeze 20+ contacts within a connector of about roughly 6mm requires very tight production tolerances which raises production costs.
    I guess most 3rd party cable/adapter manufactorers don't bother with this as long as they can sell their stuff and this might also be one of the reasons why Apples MDP-DVI adapter is so high-prized at the moment.
     

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