No graphic acceleration in OSX but perfect in win7 bootcamp (27" 2011 6970M)

Discussion in 'iMac' started by lakriz, Sep 12, 2013.

  1. lakriz macrumors newbie

    Sep 12, 2013
    Hi there..

    I have bought a 2. hand 27" imac (3,1ghz with 1gb 6970 graphics) with power supply faliure.. Replaced the power supply and put in a SSD to run OSX.. installed Lion from the disk in the box (10.6.6) on the SSD. Everything seems to work fine except from the fans.. runs full speed.. fixed it with Macs Fan Control.. super.

    Updated to 10.8.4.. seems fine..

    I play diablo 3 and hoped for a smooth gaming experince.. but no.. the imac runs D3 just as bad as my old 20" imac (9400m) (25fps with everything on low)

    I read somewhere that i should try run it in windows.. Installed win 7 in bootcamp.. on the normal harddisk.. and installed Diablo3.. and woop.. runs perfect.. highest res.. everything on high.. about 80fps.. as i expected fron this imac..

    My friend with a late 2009 27" 4850m imac runs D3 much better in OSX..

    Is it possible that i have installed a "wrong" copy of OSX.. ( i wondered if the dvd in my box is not right for my mac) though "about my mac" say the right thing.. 3,1ghz 8gb 1333mhz 6970m ect..

    Is it possible that the drivers in osx dosnt fit my mac? I get about half the point in Novabench as others with the same Mac.. (4000) others get 8000.

    I love my mac.. and osx.. and i hate to play in windows.. It just seems wrong that a "big" mac has such a lag op gfx performance in its own OS..

    Its the same in other games.. Half life2.. starcraft2..

    On youtube i can see videos that shows the same mac run D3 perfectly in OSX.. I dont think my mac has a hardware problem (just the fan problem(tested in AHT)) when it runs fine in windows..

    Hope for some answers other than " a mac is not ment to be played on" well there is probably a reason they put in a 6970 card?

    Kristian (denmark)


    I have no graphic issues.. the imac runs perfect smooth.. and all tempertures seems normal.. in windows the gpu temp increase to about 50deg when i play games.. and decrease perfect after i exit the game..
    This dosnt happen in osx.. it seems that the games dont use the GPU at all.. and i just play games with "software acceleration" and no hardware..
  2. elithrar macrumors 6502


    May 31, 2007
    Can you screenshot your Diablo 3 settings? You should be able to get better than 25FPS, but if you have shadows cranked up high or AA on max, you're still going to struggle.

    The game is more performant under Windows (better drivers + more time tuning DirectX), but we're talking about a 10-20% gap at most.
  3. lakriz thread starter macrumors newbie

    Sep 12, 2013
    There is no hardware acceleration in OSX.. it is not the game settings.. I get 80+ fps in win.. and 7 fps in osx if i put everything on max exactly as in win.. 25fps is with everything on LOW.. including no AA..

    Hope maverics can give me a better graphic performance..
  4. elithrar macrumors 6502


    May 31, 2007
    Then there is clearly a problem with your machine/install. Tried a permissions repair and/or reinstall of Diablo 3?
  5. lakriz thread starter macrumors newbie

    Sep 12, 2013
    Have tried a diablo 3 reinstall.. not sure what permission repair is.. but will google it as i write.. and try.. I wanna try reinstall OSX from the bottom.. have read about what versions of osx came with my mashine.. and it should be the right 10.6.6.. havent tried play diablo in that.. as i upgraded as the first thing.. could be interesting to install mountain lion clean..

    Must try permissions and after that reinstall..

    Thanks :)
  6. omvs macrumors 6502

    May 15, 2011
    That's weird. I have the 2GB version of that machine, and I get pretty decent gaming performance - 2560x1440 at high details on D3, Borderlands 2, etc. I can't imagine how the machine would not be using the cpu other than the OS being borked in some odd way.

    I'd vote for full re-install - if its already got 10.8 on it, do an install from recovery mode (command-r at startup) rather than starting at 10.6 and going from there.
  7. lakriz thread starter macrumors newbie

    Sep 12, 2013
    ahhh perfect suggestion.. didnt know about the recovery mode.. its reinstalling 10.8 now..

    Thanks.. :)

    I cant see it should be a hardware problem.. when it runs so well in windows.. In never gets any temperature change in osx.. so i bet it doesn't use the hardware acceleration..

    Happy to hear that an other machine runs much better..

    If this doesn't help there is probably a hardware problem.. could be OSX wont use the gfx because of the fan speed problem.. It only has one errorcode in AHT.. about the fan controller.. I''ve read it to be a new mainboard..

    In that case it must be a win-only-gaming machine.. And everything else in OSX..
  8. omvs macrumors 6502

    May 15, 2011
    That could be, especially since I just reread and saw that your were forcing the fan speed - I didn't notice that before.

    A few months ago I broke the LCD data cable, which also disconnected the LCD temperature sensor -- my fans would spin-up to max (5500RPM) and I have to use a smc override to slow them back down.

    But I also noticed the graphics performance was lousy when I only had 1 external monitor. When I had 2 external monitors hooked up it wasn't bad - might have put the graphics driver into a different mode (maybe it was a bug ;). And I think it was fine either way in Windows. Eventually I replaced the lcd cable and everything went back to working. I

    Can you rerun AHT and note which code it gives? That should indicate which sensor is problematic. Or run istat menus and see what sensors it reports - from the missing one should be able to decide what sensor isn't working.
  9. lakriz, Sep 19, 2013
    Last edited: Sep 19, 2013

    lakriz thread starter macrumors newbie

    Sep 12, 2013
    We are closing in on it.. i tried to reinstall via recovery but didnt think of erasing the drive before reinstall.. so nothing happened at all.. and i gave a little up on that.. but after that i noticed that exatly the LCD proximity sensor right after boot showed 240deg.. and as the fans fired up at max it fell to about 10deg.. in a room with 22deg.. so i took the mac apart and checked the sensor on the lcd.. and could see that the gray and black wire went into another little 4pin connector ON the lcd.. so i gave up following it back to the main board..

    But now that you write about the lcd cable.. it could be exatly my problem..
    I havent tried with two monitors..

    The error code is still


    I googled it as the Ambient temp sensor.. and that sensor is not present in any stat apps i try.. So i thought that could be the OS not showing it if the "bios" (EFI?) cant see the sensor.. and again i thought of a net main board..

    But now i have new hope.. :) If i find a thunderbolt -> DVI/HDMI adapter and try i second screen.. could be WIN.. and then a new LCD cable..

    Ahh you say 2 external monitors.. that means 1 is not enough.. and then yeah that could be a bug it dont count the temp failure in with 2 externals..

    I bet that is precise the failure in my MAC.. i will find another lcd cable.. i guess that is the long thin one running first horizontally and then vertically down and is connected with a little metal "spring" on the graphic card..
  10. omvs macrumors 6502

    May 15, 2011
    Yep, TA0P is definitely the ambient sensor ( - if its not showing up in any programs, it probably means the sensor failed/disconnected.

    When my LCD went out, I got the TL0P error, and the LCD prox sensor did not appear in iStat Menus (different sensor then yours). So it won't be the LCD cable, unless that doesn't work for you either.

    I think step 27 here shows the ambient temp sensor connection - its the one near the CPU in the bottom left:

    You might want to check and see if its plugged in... Worst comes to worse, order another sensor off the web (could be any of them), hook it up, and position it wherever convenient.

    BTW: As far as the 2 monitor trick, I'm not sure if that'll work for you - remember, my built-in panel wasn't hooked up at that point, and I'm guessing yours still works fine :) You might get the same affect with 1 or 2 externals + internal, but maybe not - could be i just hit a bug in the driver where it started ignoring the SMC error. I'd say your best bet is still to replace the sensor.

    BTW: It sounds like you've opened it up before and know what you're doing, but I'd say be extra careful around that !$@#! LCD data cable. It wasn't that hard to break, though fortunately its not that expensive to replace either.
  11. Brian33 macrumors 6502a

    Apr 30, 2008
    USA (Virginia)

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11 September 12, 2013