Performance with dual monitors on ATI 4870

Discussion in 'Mac Pro' started by Markleshark, Jun 16, 2009.

  1. Markleshark macrumors 603

    Markleshark

    Joined:
    Aug 15, 2006
    Location:
    Carlisle, Up Norf!
    #1
    Hello,

    I recently purchased a second 22" Dell 2209WA to go with my mac pro. They are both running from the ATI Radeon 4870 on my Mac Pro (2009 Quad) but the Expose performance seems to be really quite poor. Displaying all the windows is very juddery and not smooth at all. Is that what I should be expecting now? I wouldn't have on a £2000 Machine. Going into Spaces is fine, it's just Expose thats poor.

    Thanks,
    Mark.
     
  2. kellen macrumors 68020

    kellen

    Joined:
    Aug 11, 2006
    Location:
    Seattle, WA
    #2
    Odd. I have a 23" ACD and a generic 22" and they both work fine.

    Are you using a an Apple 4870 or flashed?

    Is the other monitor using a Mini Display port to dual link DVI or just to DVI? People have had some problems with the dual link DVI.

    If only on one monitor, try switching the outputs from the 4870.
     
  3. Markleshark thread starter macrumors 603

    Markleshark

    Joined:
    Aug 15, 2006
    Location:
    Carlisle, Up Norf!
    #3
    It's an Apple 4870, all that I've added is hard drives.

    I'm using one monitor with the DVI and the other with the Apple Mini DisplayPort to DVI thingy ma jig.

    I seem to be getting lag on both monitors. Have opened Windows on both sides and then one and the other, it's lagging everywhere.

    I'll try recording a video with SnapsPro see if it shows it.
     
  4. Tesselator macrumors 601

    Tesselator

    Joined:
    Jan 9, 2008
    Location:
    Japan
    #4
    I run dual 24" monitors at 1920x1200 on a 7300GT and I don't see how Expose could be any faster. It screams! Even with heavy apps and/or video in every window.

    Extremely smooth!

    <shrug>
     
  5. sparkie7 macrumors 68000

    sparkie7

    Joined:
    Oct 17, 2008
    #5
    I run 2x30" ACDs off my 4870. No lags and I have lots of windows open sometimes. The MDP to DL DVI adpater is a POS. It flickers every 20-30 minutes. It really p*sses me off especially having to pay extra for it and it doesn't work 100% :mad:
     
  6. Zokim macrumors member

    Joined:
    Jun 14, 2009
    Location:
    New York
    #6
    Mac Pro, 4870 with 2x 23" Cinema Displays

    Mine work fine, no flickering or any issues at all...besides hearing the fan in the box.
     
  7. sparkie7 macrumors 68000

    sparkie7

    Joined:
    Oct 17, 2008
    #7
    thats b/c you probably dont have the DL version
     
  8. Markleshark thread starter macrumors 603

    Markleshark

    Joined:
    Aug 15, 2006
    Location:
    Carlisle, Up Norf!
    #8
    Strange. Dunno why I get the jaggy lag then. It doesn't really show on a screen capture movie either, but it's certainly there.
     
  9. Tesselator macrumors 601

    Tesselator

    Joined:
    Jan 9, 2008
    Location:
    Japan
    #9
    You mean you can't capture the laggyness on a screen recording utility?

    OK.

    If you wanna know why this is happening (in order to possibly fix the problem) you can download and use the free "Instruments" utility found in the XCode Tools dev distribution here: http://developer.apple.com/technology/Xcode.html You have to fill out a form but other than than it's free. It's useful. Anyway it will allow you to profile just OpenGL, just the CoreGFX, etc. etc. in order to isolate what's hitting your resources hard enough to lag it.
     
  10. Markleshark thread starter macrumors 603

    Markleshark

    Joined:
    Aug 15, 2006
    Location:
    Carlisle, Up Norf!
    #10
    Ok, so have xcode installed, but I'm not sure how to use Instruments... Where do I go from here.

    Thanks in advance. :D
     
  11. thepawn macrumors 6502

    thepawn

    Joined:
    May 27, 2009
    #11
    I run a 30" on the DVI and a 27" on the DCP->DVI side and I don't have any lags.
     

Share This Page