Weird Fan (10.11.x/Metal?) kickup bug & weirder solution

Discussion in 'Mac Pro' started by ZombiePhysicist, Oct 29, 2015.

  1. ZombiePhysicist macrumors 6502

    ZombiePhysicist

    Joined:
    May 22, 2014
    #1
    So weird thing is after a reboot, the video on my 6 screen setup is very snappy. It seems like metal is active as when you use Mission Control 4 finger gesture to move all windows half way off screen and then back (doing that back and forth with the magic trackpad 2) is very liquid smooth. However when you move things half way off the screen and stop before you get them all off screen, and just keep all the windows 'hovering' halfway off, you hear the fans on the video card really kick up. Also, I use OmniDazzle pixie dust mode, and when I streak pixie dust and keep the pixie dust continuously dusting, the fans also kick-up to full gail.

    Odd, right. But you might just write that off to, maybe the card is an 'edge case' in that the MacPro isn't really optimized to make use of that card well.

    But here is the weird kicker. If you run Elder Scrolls Online, and then quit, it cures the problem. No more fan kick up, although, the (metal?) acceleration seems to be a little less smooth afterwards. Potentially, maybe Elder Scrolls either loads some library needed by the video card, or kills something (metal libraries) that are taxing the card? No clue why this is the case.

    One other weird wrinkle is my USB 3.0 card seems to affect things. When I use my old Inateck USB 3.0 card, the fans take longer to kick-up and kick-up less frequently than when I use my Allegro Pro USB 3.0 card. My guess is the Allegro draws more power.

    Anyway, anyone have any clue what the heck is going on? I don't reboot too often so the "Elder Scrolls" solution to killing the fan problem isn't a big deal, but it's really super weird.

    Here are the specs of my setup in case it makes a difference (and it might):

    Mac Pro 2010/5,1
    128GB RAM @1333MHz
    8TB (QTY 2) in SATA 2 sleds nos. 1&2
    512GB OWC Mercury in SATA 2 sled no. 4
    VisionTek AMD RADEON HD7870 Eyefinity 6 (no flash, no boot screen, PC card) in Slot 1
    Sonnet Technologies Sonnet Allegro USB 3.0 4 Port PCIe Card USB3-PRO-4PM-E in Slot 3
    Addonics Quad mSATA PCIe SSD 4TB SSD in Slot 4
     
  2. ZombiePhysicist thread starter macrumors 6502

    ZombiePhysicist

    Joined:
    May 22, 2014
  3. ActionableMango macrumors 604

    ActionableMango

    Joined:
    Sep 21, 2010
    #3
    Someone, I think ScottishCaptain, did a lot of investigation into strange PCIe fan behavior that was fixed by putting a load on the GPU. He was in communication for a while with Apple Engineers and determined that there was a bug in the SMC firmware, possibility linked to backplane power consumption. I don't know how much of it was speculation or proven. I tried to help with some tests on the power consumption angle, but the results were not conclusive.

    I see a lot of parallels in your post (fan speed, GPU use, and power consumption). However, it's always been about the PCIe fan, not the GPU fan as you state. Are you certain it is the GPU fan you are hearing?
     
  4. ZombiePhysicist thread starter macrumors 6502

    ZombiePhysicist

    Joined:
    May 22, 2014
    #4
    No, I just assumed it was that since it's a new card. Let me check and I'l ping back here.

    The weird thing is, after you put the load on the system, the fan issue goes away. But the graphics windowing system doesn't run as smooth and fast as it it did prior to the 'Elder scrolls' fix. It still runs decently fast (and certainly still way faster than the 5770s i had in there) so I'm ok with it. Just weird all around.

    Good to hear that I'm not totally out of my mind on this. Thanks so much AM!
     
  5. ActionableMango macrumors 604

    ActionableMango

    Joined:
    Sep 21, 2010
    #5
  6. ZombiePhysicist thread starter macrumors 6502

    ZombiePhysicist

    Joined:
    May 22, 2014
    #6
    So confirmed, it definitely is the video card fans that kick up. But as soon as I run elder scrolls and quit, the machine is fine until I reboot. Bizarre.
     

Share This Page