Radeon 7950 Questions. About to Pull the Trigger.

Discussion in 'Mac Pro' started by sammyman, Apr 1, 2015.

  1. sammyman macrumors 6502a

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    #1
    I have been reading a lot about this graphics card, and am close to buying one. I have a few questions before I pull the trigger.

    1. Is this card supported on a 2009? On everymac.com says "Please note that the Sapphire Radeon HD 7950 only is compatible with the "Mid-2010" and "Mid-2012" Mac Pro models."

    http://www.everymac.com/systems/app...ics-cards-dvi-dual-link-mini-displayport.html

    I have a 2009 with a 2010 firmware with a 3.33GHz 6 core. Will this card work on mine?

    2. I'm leaning towards a PC version. I read that the big difference is that you lose the apple boot screen. I'm not terribly worried about that. So can I buy a cheaper PC version, and just plug it in without flashing it?

    3. Is there a "most compatible" version of 7950 (aside from the mac version)? I see the two fan version, the one fan version (red/black), twin frozr, power cooler.

    My gameplan is to spend the least amount of money to start running 3 x u2412m monitors by buying a PC version. I'll try to flash it down the road if needed, but right now I'm not confident I can do it. This is all overwhelming, so I appreciate your help.
     
  2. Macsonic macrumors 65816

    Macsonic

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    #2
    Hi Sammyman. The AMD 7950 will work on your 2009 Mac Pro regardless of what is indicated in EveryMac.com. There is a member here using the 7950, one on his 2009 Mac Pro though I think his is the Mac Edition version. MacVidcards is offering the AMD 7950 http://www.macvidcards.com/store/p12/AMD_Radeon_7950_3_GB.html I recall a few months back the 7950 was sold out in his store.

    He has the 2 card designs you mentioned, the large twin fans and the red/black with the cooler fan. I am not a techie guy though I think the twin fan design runs cooler than the red/black with one fan. The red black design pushes the heat towards the back part of the card outwards the Mac Pro case, similar to your Ati 5870 card. Unless I am mistaken, the twin fan version pushes the heat upwards and sideways ( not sure ). As far as I know, with the twin fan, the computer enclosure must have a good ventilation.
     
  3. h9826790 macrumors 604

    h9826790

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    #3
    IMO, the reference design (the single fan one) should be "more compatible" because the Mac Edition is base on that one.

    However, usually those after market design has better cooling and performance.

    Anyway, my Mac Pro is the 2009 version, and able to run the 7950 Mac Edition card before I apply the 5,1 firmware upgrade. I think the real limitation is the OSX version, but not 2009 or 2010/2.

    However, AFAIK the HDMI audio ONLY works with the 5,1 firmware (with 3rd party driver installed) but still regardless if that's a 2009 or 2010/2 machine.
     
  4. MentalVizion macrumors regular

    MentalVizion

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    #4
    I don't know if the Radeon HD 7950 is significantly cheaper then the GTX 680, however with the 680 you have the advantage of being able to flash it yourself, thus enabling the bootscreen. Also, it is quite a bit stronger IIRC.
    It was even better then the 7970 i think.

    I know I sound like THE 680 worshiper, but it just seems to be the smartest solution most of the time :D
     
  5. fuchsdh macrumors 6502a

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    #5
    I bought my flashed PC 7950 off eBay, and it worked fine in my 3,1 and now 5,1. Your 4,1 will be fine with it. (I believe I've got the Frozen something or rather SKU. It's still got the mini-DP connections off the back though, which saved me some adapters.)

    They're fairly equivalent cards in stock configs, with the 680 having a slight edge in gaming and the 7950 in computing tasks. Personally for me the latter boost and the extra 1GB of memory made it more attractive, but I haven't been looking at prices recently so I'm not sure if one's more price-efficient at this point, or how much the differences between the cards are minimized/exaggerated via overlocking or different SKUs.
     
  6. sammyman thread starter macrumors 6502a

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    #6
    So it sounds like I'll stick with the most stock design, the red/black one with one fan.

    So I can buy an unflashed 7950, plug it in and be ok.. just sacrifice the bootscreen?

    Are you saying you can't flash the 7950 yourself? Or is it much more difficult to flash yourself? Based on everything I've read here, I'm still drawn to the 7950.
     
  7. MentalVizion macrumors regular

    MentalVizion

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    #7
    Should work fine, yea. I don't know how thinks work driver-wise on the ATI side, but I can imagine them being built in already.

    Also, maybe it is possible flash the 7950 yourself aswell. Since it also got a "mac edition" release.
     
  8. TheStork macrumors regular

    TheStork

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    #8
    I bought a Sapphire 7950 single fan, Reference Design card from eBay for less than $100 shipped last Fall. I tested it out and then sent it to MacVidCards for flashing. It works flawlessly (as best I can tell) in my 2008 Mac Pro (3,1).

    I decided to have MVC flash it instead of following the flashing guide at netkas' forums because, by the time I would have it flashed and working, I would have paid myself twice what MVC charges for flashing the 7960. YMMV.
     
  9. Pieterr macrumors regular

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    #9
  10. sammyman thread starter macrumors 6502a

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    #10
    No, too expensive. I'm limiting myself to $200 tops.

    So just to be clear, people are paying an extra $115 to MVC to flash it, just to have the apple bootscreen? PC cards work flawlessly aside from the apple logo on startup, right?
     
  11. fuchsdh macrumors 6502a

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    #11
    Yep. If you have another Mac graphics card in your computer, that removes the issues with boot screens as well (hence why the low-profile GT120s are popular.)
     
  12. sammyman thread starter macrumors 6502a

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    #12
    I have the GT120 right now! I was going to sell it when I upgrade, but it probably makes more sense to leave it plugged in. So I can have one monitor on the old card, and two on the new card?

    Sounds like a game plan. I'm buying the cheapest 7950 / 7970 I can get my hands on (preferably with a one fan design).

    Thanks everyone. If you have any other tips, please let me know. The amount of threads and data on this is overwhelming for a noob.
     
  13. fuchsdh macrumors 6502a

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    #13
    The 7950 can handle at least three displays; someone can correct me if I'm wrong (as this is out of my wheelhouse), but I think all you need the GT120 to do is sit in a slot for the boot screen—you don't actually have to drive a monitor with it.
     
  14. m4v3r1ck macrumors 68020

    m4v3r1ck

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    #14
    Radeon 7950 Questions. About to Pull the Trigger.


    I have an old XT 2600 HD, original Mac Pro 2008 GPU, hooked on an even older Samsung Syncmaster 19" monitor, just for bootscreens and/or maintenance e.g. booting in verbose mode etc. My PC GTX 670 drives a 24" and a 22" monitor.

    IIRC I have never heard of the "Mac GPU just sit a PCIe slot" solution working without a cable for bootscreens.

    Cheers
     
  15. crjackson2134 macrumors 68020

    crjackson2134

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    #15
    I went for the 7970 from MVC instead of the 7950. Besides flashing the card, he also modifies it for 5GT/s as opposed to 2.5GT/s that PC cards get when installed in a MP. You also get a professionally disassembled and cleaned and thoroughly tested card with a warranty.

    For me it was truly Plug-N-Play. I didn't even need to reset NVRAM/SMC. It was perfect out of the box, and cost about the same that you are going to spend by making an eBay purchase and paying for his flashing service.
     
  16. MentalVizion macrumors regular

    MentalVizion

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    #16
    You can hook your screens up this way. However, I think everything the monitor connected to the GT120 will output, won't benefit from the 7950's power.

    That's why I ditched this method and went for the DIY flash route as I originally planned to run a non-flashed 680 + GT120 aswell.
    But as soon as I read that it is possible to flash the 680 yourself, I instantly dropped the GT120. Also, some people said it rather hurts overall performance rather then increases it. You also save one PCIe slot this way. ;)

    BTW: Save yourself that GT120 as you won't get much money out of it anyways.

    That's actually quite interesting. However I honestly don't think it will work.
    I guess in order to have the bootscreen you have to drive one screen through the GT120.

    It should run at 5GT/s at OS X by default. However, in order to get the full 5GT/s in windows aswell it needs to get flashed.

    OP: If I were you I'd probably still get myself either a 2GB or a 4GB GTX680 :D
    I guess you can get the 2GB models on craigslist for like 140ish$.
     
  17. Pieterr macrumors regular

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    #17
  18. sammyman thread starter macrumors 6502a

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    #18
    This thread has given me some good info. I think I prefer the mini displayport outputs of the 7950/7970 over the hdmi/dvi imports of the 680. Plus, I'm not as much a gamer so the 7950 may be better for me anyway.

    I read somewhere about removing a resister to get 5gt/s performance. I wonder if it needs the resistor removed + the flash, or just the resistor removed? I'm confident I could remove the resistor myself.
     
  19. Keter macrumors member

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    Jan 30, 2015
    #19
    For $200 I can provide you a flashed EVGA GTX 680 SC.

    Since it is the Superclocked model 02G-P4-2682-KR you get a bit better performance over the Mac Edition.

    GPU
    1058 MHz GPU Base Clock
    1124MHz Boost Clock


    Memory
    2048 MB, 256 bit GDDR5
    6208 MHz (effective)
    198.66 GB/s Memory Bandwidth

    [​IMG]

    [​IMG]

    [​IMG]

    PM me if interested
     
  20. crjackson2134 macrumors 68020

    crjackson2134

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    #20
    It's the R17 resistor, read about the MOD here.
     
  21. Keter macrumors member

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    Jan 30, 2015
    #21

    If you are connecting any displays that are greater than 1080P DVI or Displayport is the best method. If going 4K Displayport is the only method to get 60hz.

    You need to remove the R17 resistor on the 7950 to achieve 5GT/s link speed. One can achieve the same with the flashing done by MacVidCards.

    Without a 5GT/s link speed you are essentially crippling your upgrade to half of its performance.
     
  22. sammyman thread starter macrumors 6502a

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    #22
  23. Keter macrumors member

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    Jan 30, 2015
    #23
    For a 7950 you will need a 6 pin and a 8 pin, unless it is a reference design you wil only need two 6pin cables.

    Personally I think it is a bad idea to run the 6 to 8 pin cables because it can stress the backplane board if the card demands the extra voltage that the system was not built to provide. Many others will disagree with me on this due to their experience.

    The way I see it, you're opening yourself to additional possibility of issues on top of the potentials from the modifications already performed.

    ----------

    If you are dead set on a 7950 here is an option:


    http://www.ebay.com/itm/AMD-Radeon-...460?pt=LH_DefaultDomain_0&hash=item1e9c6721e4

    They are accepting Best Offer
     
  24. MentalVizion macrumors regular

    MentalVizion

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    #24
    Does the 7950 not work out of the box with 5GT/s speeds in OS X? :O
    I thought the EFI flashing just enables it for windows?
     
  25. crjackson2134, Apr 2, 2015
    Last edited: Apr 2, 2015

    crjackson2134 macrumors 68020

    crjackson2134

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    #25
    Correct, to my knowledge nVidia uses soft hooks, AMD uses hardware (resistors). Flashing gets you efi but it's only 2.5 GT/s until the resistor mod.

    Also, the reference card doesn't require any 6/8 pin adapters. Just plug in the 6-pin cable and the card works. It's designed to accept either, and it won't over power your 6-pin connection but you need the single fan (red) reference card as far as I know. I'm speaking specifically about the HD7970.
     

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