Screen Goes Black/Flicker on 9400m (Late 08 MPB)

Discussion in 'MacBook Pro' started by arjunlall, Oct 31, 2008.

  1. arjunlall macrumors newbie

    Joined:
    Oct 31, 2008
    #1
    So I got a new Late 08 MBP 2.8 earlier this week. Everything has been great except that occasionally (once or twice an hour) my laptop screen will go black for about 200-300ms and then come back. Often only the top 1/2 or top 3/4 of the screen will go black. I was worried it was the LCD, but today I switched over to the 9600gt for the first time and the problem seems to have gone away. I generally code all day and havent been doing anything intense when the flickers happen, the CPU/GPU temps are also low.

    I have an external monitor hooked up. Ive only noticed the problem when the external monitor was hooked up but then again 90% of the time I use the computer it has the external plugged in.

    Anyone else notice this?

    Also does anyone know if the 9400m's 256mb of memory is shared with the main RAM, ie if I am running on the 9400 do I only have access to about 3.74 gigs of ram?
     
  2. ozone23 macrumors newbie

    Joined:
    Jul 30, 2008
    #2
    Srceen flickers on 9400

    Hi,

    same problem here:

    I got the new MBP with the 512 MB Nvidia9600 (also late Oct08) but when i switch to the 9400 The Display goes black/flickers once in while for a few ms. But only 1/3 of the top screen.

    Running on the 9600GT the Display works fine. In really hope this is just some driver problem.

    Anybody else noticed this problem?

    cheers

    o3
     
  3. macrem macrumors 65816

    macrem

    Joined:
    Mar 11, 2008
  4. ozone23 macrumors newbie

    Joined:
    Jul 30, 2008
    #4
    After resetting the System Management Controller and reinstalling OS X the problem still exists.
    I´m getting my MBP replaced from apple support.

    cheers

    o3

    ps.: two thumbs up for the support workers @:apple:, definitely one of the best support-centers i ever talked to.
     
  5. danny_w macrumors 601

    Joined:
    Mar 8, 2005
    Location:
    Austin, TX
    #5
    There have been a great many issues with the 9400m on both MB and MBP on the Apple forums. Most of the problem that I have seen relate to using an external monitor and the screen not waking properly after sleep, or flashing at random times (even with Apple branded displays). However, I have seen some reports without an external display. You might want to check:

    http://discussions.apple.com/category.jspa?categoryID=249
     
  6. mct74 macrumors member

    Joined:
    Aug 15, 2008
    #6
    I am having the same problem with my 2.53Ghz MBP - when using external display with the 9400 card, the external display blanks out for a second every now and then...

    Using the 9600 card, all works well...

    Question - once you had the laptop replaced, did the problem go away?

    Any thoughts on why this is happening?

    Would rather not replace the laptop if possible (possible software issue?).
     
  7. danny_w macrumors 601

    Joined:
    Mar 8, 2005
    Location:
    Austin, TX
    #7
    I think there have been some reports on the Apple forums of people exchanging the units with no improvement. I haven't read a report where somebody exchanged and the problem went away.
     
  8. ozone23 macrumors newbie

    Joined:
    Jul 30, 2008
    #8
    just want to mention that the problem appears here not on some external display, but the builtin one! Yesterday evening it went black even every 5 seconds.
    It´s impossible to work like that until i switch to the 9600 so i do expect an improvement after the exchange ;)

    Since the 9400 uses shared memory it can be also some ram issue i guess..

    cheers

    o3
     
  9. mct74 macrumors member

    Joined:
    Aug 15, 2008
    #9
    wow - I have not had the built-in display exhibit that behavior - only the external display. Would be curious to hear your experience with the new laptop.
     
  10. New2MacMBP macrumors newbie

    Joined:
    Oct 13, 2008
    Location:
    Phoenix, AZ
    #10
    Built In Screen Flicker

    Similar problem for me with the built in (haven't noticed it on the external). When running on the 9400m if I'm scrolling up/down on longer documents, web pages, spreadsheets I get either partial or full screen flicker. The most frequent (can replicate 75-80% of the time) is a set of 10-20 1 to 3 pixel wide horizontal lines mostly pronounced on the left side, mid screen. As soon as I quit scrolling they are instantly gone and I don't see them when on the 9600m. I'm guessing this is a performance or driver issue and not something that would be fixed by sending it in so I'm sitting on the one I have till either better drivers come out or their is a formal diagnosis. It's the only issue I'm having and I use mine everyday (not to mention all the work to get it setup the way I want it).
     
  11. liuhui51511 macrumors newbie

    Joined:
    Oct 21, 2008
    #11
    hi friend! i had the same problem with my first new mbp, everything was perfect apart from the top half of the screen flicks once every 20mins or sometimes could be more often, i went to the apple store and had it exchanged, my new one now is ok!
     
  12. mct74 macrumors member

    Joined:
    Aug 15, 2008
    #12
    Have you tested this with the 9400 graphics card and an external monitor? Wondering if you notice the screen going black on the external display after a few minutes when using the low-end graphics...
     
  13. mct74 macrumors member

    Joined:
    Aug 15, 2008
    #13
    I just called Apple Support and they had me reset the system by taking the battery out and pressing power button for 10 seconds and then hook everything back up and power machine on while holding the CMD, Option, P and R keys until I heard the Apple chime 3 times. Seemed to help at first since I went for 20 minutes without the external monitor blanking out. Then... it happened again :(. I am using a display port-VGA adapter. Tomorrow I am going to try a display port-DVI adapter and see if there is any difference. I at least have a case ID open on this...
     
  14. PabloGS macrumors member

    Joined:
    Oct 29, 2007
    Location:
    Europe
    #14
    Well... I might be a bit off topic here, since I haven't noticed the flickering yet, but using the 9600GT and quickview in Finder (hit the Space bar) produces a garbaged screen in some cases. It is reproducable but I couldn't pinpoint it exactly just yet.

    So I was wondering if anybody was experiencing similar issues... :(

    Greetings,

    Pablo
     

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  15. mct74 macrumors member

    Joined:
    Aug 15, 2008
    #15
    Ok I think I may have stumbled on something with regards to the external monitor blanking out intermittently.

    Today I brought my MBP to my office where I have an Optiquest Q20wb monitor. I hooked it up and sure enough, I have not had the screen blank out the whole day so far (it has been 6 hours so far and usually the issue pops up after 5 - 20 minutes).

    I checked the display settings and found an interesting tidbit - this screen has a refresh rate of 60, where my Samsung Syncmaster 20" LCD at home shows up with a refresh rate of 59.9. Both have the same resolution of 1680 x 1050, so I am thinking the problem stems from issues in compatibility with the 59.9 refresh rate when using the 9400 video card.

    Anyone else who is having this issue - can you post your refresh rates and resolutions as well as your LCD model info?
     
  16. ogdoad8 macrumors newbie

    Joined:
    Nov 7, 2008
    #16
    My 9400 ("Better Battery Life") regularly snows up my external Viewsonic LCD at 1600x1200, and it's at 60 Hz.
    My 9600 ("Higher Performance") has no problems.

    FYI there are a few discussions on this going on on the Apple Support Forums:

    http://discussions.apple.com/thread.jspa?threadID=1778280
    http://discussions.apple.com/thread.jspa?threadID=1760586
    http://discussions.apple.com/thread.jspa?messageID=8338326
    http://discussions.apple.com/message.jspa?messageID=8408745

    I opened a case with Apple Support. They didn't have any solution, but it's imperative that everybody having this issue call Apple Support and let them know and make sure they open a case!!! This is the only way we have a chance of getting this problem fixed.
     
  17. virtuatony macrumors regular

    Joined:
    Mar 9, 2008
    Location:
    Canada
    #17
    Mine flickered on the main display at low brightness settings, so Apple said it was DOA.

    However I don't have one of those cool mini-displayport to DVI converters to try it on an external display.
     
  18. jasonrm macrumors member

    jasonrm

    Joined:
    Jan 26, 2008
    Location:
    Arizona, U.S.A.
    #18
    I'm also having this issue... but I'm hesitant to take it in just yet as I seem to have no issue at all while running on the 9600M GT.

    Wondering if it is just a frame buffer/memory issue that needs to be sorted out with an update or if it is a symptom of a hardware failure.

    Mostly I just don't want to drive 1 1/2 hours to go to an Apple store...
     
  19. mct74 macrumors member

    Joined:
    Aug 15, 2008
    #19
    Issue Identified - Driver Issue Most Likely Cause

    So I decided to go to the Apple Store to do some testing with a Genius with my laptop and my Samsung monitor. We hooked up my late 2008 MBP laptop in the store to the Samsung 206BW LCD and after 15 minutes, it blanked out. I told the Genius that the issue does not seem to be present with my Optiquest LCD so nVidia driver compatibility with the Samsung LCD is looking most likely.

    We then decided to hook up the Samsung LCD to another MacBook Pro in the store to see what would happen (a display unit). With the 9600 card activated, the monitor performed fine. However, when we changed to "Better Battery Life" mode, activating the 9400 video card, caused the MacBook Pro to actually crash and reboot!! When it came back up, the video card setting was set back to "Bettery Graphics Performance". We checked the installed updates on the MacBook Pro and the one in the store did not have the MacBook Pro 2.1 update which fixes compatibility issues with some external displays.

    It is apparent that the 2.1 update helps the laptop not crash when the 9400 card is activated while hooked up to a Samsung 206BW LCD, however, it is also apparent that the update does not solve all the issues with compatibility, as the refresh rate is detected incorrectly (59.9 instead of 60) and the screen blanks out intermittently as a result of what looks like the video card sending a refresh rate that is out of range of the monitor's capability.

    They took my information and are going to escalate the issue to the engineers to hopefully get a fix pushed out as this may also affect other LCD's that are based on similar components as the Samsung displays.

    Bottom line - don't bother swapping laptops if you are experiencing this issue on your external display. Hopefully a software update will be out soon. Now, if you are having an issue with your built-in display - that is a whole other story. Hope this info helps!
     
  20. smokedog macrumors regular

    Joined:
    Oct 26, 2008
    Location:
    UK
    #20
    I'm having the same problem and wondering if I should return it. It only happens when using the 9400 gfx card at low brightness, could it be a driver problem?
     
  21. Firefly2002 macrumors 65816

    Joined:
    Jan 9, 2008
    #21
    Wouldn't be terribly surprised to see the 9x00 series fail like the 8x00....
     
  22. mct74 macrumors member

    Joined:
    Aug 15, 2008
    #22
    Very well could, but at least in the issue I am seeing, it does not look like faulty hardware, but rather bad drivers....
     
  23. ozone23 macrumors newbie

    Joined:
    Jul 30, 2008
    #23
    @mct74: I don´t understand why you are keep posting with your OT issue.. :confused:

    This will confuse the people having the same issue like the author of the thread. There are so many discussions here on macrumors and on the apple support forums regarding the external monitor issue but as far as i searched this thread is the only one about the INTERNAL display flicker...

    so i want to mention again: we are having problems with the internal - builtin display when running on the 9400 Chip. No external display is involved...

    cheers

    o3

    ps.: i will keep you uptodate if the exchange helped me since i am still waiting for the replacement device...
     
  24. mct74 macrumors member

    Joined:
    Aug 15, 2008
    #24

    Sorry - I thought the original poster stated the issue he had was when his external monitor was hooked up. I must have misunderstood that his issue is with his built-in monitor only. I did do searches of the forums before posting replies and this was the only one I found relevant at the time.

    Hmmm.... I still don't think this is off-topic, however, ESPECIALLY after my findings at the Apple Store where the MBP actually crashed and rebooted with a certain external display. This pretty much shows that the late 2008 MBP's using the 9400 GPU does some whacky things depending on what kind of external LCD is attached, which updates you are running, etc.

    Regardless, I was just trying to post some useful information in a thread, which I thought was relevant. Sorry again...
     
  25. Firefly2002 macrumors 65816

    Joined:
    Jan 9, 2008
    #25
    I hope that's true
     

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