intel 4000 vRAM question.

Discussion in 'MacBook Pro' started by Techno Pirate, Aug 18, 2012.

  1. Techno Pirate macrumors newbie

    Joined:
    Jul 29, 2012
    #1
    I have the 2012 baseline 13in June macbook pro with 4gb and an i5. I checked out the my intel 4000's vRam and it says 384mb where as the beefier i7 model with 8gb at the apple store reported 512mb of vRAM. That's a pretty large difference in certain applications, performance wise, so I wanted to make sure of something. Is it true that If I upgrade my ram from 4gb to 8gb the vRAM the intel 4000 borrows goes up to 512mb from 384mb? I remember that happening in one of the previous macbook pro models with a different intel GPU. Or maybe it's only in the i7 model. Thanks

    Al
     
  2. gentlefury macrumors 68030

    Joined:
    Jul 21, 2011
    Location:
    Los Angeles, CA
    #2
    Yes, the more ram you have the more vram you get. Apple limits the hd4000 to 512MB which is reached at 8gb.
     
  3. thekev macrumors 604

    thekev

    Joined:
    Aug 5, 2010
    #3
    Something is very wrong with your math:p.
     
  4. gentlefury macrumors 68030

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    Jul 21, 2011
    Location:
    Los Angeles, CA
    #4
    Sorry, fixed
     
  5. thekev macrumors 604

    thekev

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    Aug 5, 2010
    #5
    I was just having fun with it.
     
  6. yusukeaoki macrumors 68030

    yusukeaoki

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    Mar 22, 2011
    Location:
    Tokyo, Japan
    #6
    Yeah it would be cool if more RAM= more VRAM but thats not how it works.

    4GB is 384MB, 8GB and above is all 512MB.

    This is same with the old intel HD 3000
     
  7. Techno Pirate thread starter macrumors newbie

    Joined:
    Jul 29, 2012
    #7
    Cool thanks guys and gals.
     
  8. tmt macrumors member

    tmt

    Joined:
    Mar 8, 2009
    #8
    Sorry to hijack the thread but why is the intel gpu limited to 512 mb? I was looking forward in putting in 16 Gb into mine ;)
    /J
     
  9. dusk007 macrumors 68040

    dusk007

    Joined:
    Dec 5, 2009
    #9
    Because it is not really fast enough for a detail level that would require more VRAM anyway.
    Also since it has no dedicated RAM access to System memory is much less troublesome for the HD 4000 than for say 650M.
    It has full speed access to the LLC aka L3 and the copy path from to memory is full speed low latency (direct). There is no latency problem or limited bandwidth as the x8 PCIe lanes pose. A 650M needs to pull data over the PCIe lanes which is a much longer way and slower. The Intel GPU practically has full speed access to the system memory. You can do a lot with drivers here.

    More VRAM just is of little to no use and limits how much RAM you can use for the OS. It cannot be dynamically adjusted at runtime thus it would be foolish to make it any bigger than reasonable.
     
  10. tmt macrumors member

    tmt

    Joined:
    Mar 8, 2009
    #10
    Thanx 007 for the reply.
    It makes sense to me now :D
    /J
     

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