NVIDIA GeForce GTX 675MX vs GTX680MX ?

Discussion in 'iMac' started by rainbowsofwhite, Nov 8, 2012.

  1. macrumors 6502

    Joined:
    Jul 21, 2011
    #1
    Hi everyone,

    Planning my configuration spec sheet for the highly anticipated iMac 27 in Dec.
    I'm slightly stumped on the two high end graphics cards available.

    Could someone (more technically minded than me) shed some light on the difference between the NVIDIA GeForce GTX 675MX (1 GB of GDDR5) and NVIDIA GeForce GTX 680MX (2GB of GDDR5).

    Why would you choose one over the other.

    Gaming perhaps?
     
  2. macrumors 6502

    Joined:
    Oct 3, 2010
    Location:
    Maryland US
    #2
    Both are very good cards for gaming... The x at the end of those card names means their actually underclocked desktop versions. I personally would go for the 2gb option because it will handle rendering games at higher resolutions better like the native resolution on the 27 inch.
     
  3. thread starter macrumors 6502

    Joined:
    Jul 21, 2011
    #3
    Thanks for your reply and info.

    It'll be interesting to see how much more $$$ we'll need
    for the 2GB option.
     
  4. macrumors 6502a

    Ice Dragon

    Joined:
    Jun 16, 2009
    #4
    If it is not too much, absolutely go for the 2 GB 680MX option without question.
     
  5. thread starter macrumors 6502

    Joined:
    Jul 21, 2011
    #5
    Would the GTX 680MX use a lot more power or create more heat?
     
  6. macrumors 6502

    boto

    Joined:
    Jun 4, 2012
    #6
    The GTX 680MX uses 122 Watt, whereas the GTX 675MX requires 100 Watt so we can expect more heat and higher temperatures. However, it is unclear what new cooling system the new iMac uses and how efficient it is. It may even be possible that the GTX 680MX configured iMac will use a special power supply and cooling system to manage it. Nonetheless, if you are a dedicated gamer or need such performance than make the purchase immediately. There are probably a limited quantity since this is an exclusive GPU offered for the iMac only, and I have yet to see other vendors offering this option.
     
  7. thread starter macrumors 6502

    Joined:
    Jul 21, 2011
    #7
    Excellent detailed response, thanks.
     
  8. macrumors 68040

    MythicFrost

    Joined:
    Mar 11, 2009
    Location:
    Australia
    #8
    Have a look at notebookcheck. The GTX 680MX and GTX 675MX are both on that chart, though only the latter has any benchmarks yet.
     
  9. macrumors member

    Joined:
    Feb 29, 2012
    Location:
    Oxford UK
    #9
    Hello. Possibly a silly question..

    That chart had the 675 and 680 benchmarks but does the 675 always have 1gb and the 680 have 2gb? Or can that change and those benchmarks are both based on 2gb etc.

    I know nowt about GPU...
     
  10. macrumors regular

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    Sep 26, 2012
    Location:
    Caotbridge (outside Glasgow, UK)
  11. macrumors 6502

    Joined:
    Dec 20, 2010
    Location:
    Berlin
    #11
    I'm also not sure which one to get, but will wait for the final prices before I can make a safe decision.

    According to wikipedia the 675MX has a maximum of 1152 GFLOPS processing power, whereas the 680MX doubles this to 2234.3 GFLOPS. Of course these are theoretical achievable performance numbers, so I wouldn't count on double the performance. None the less this is very exciting for games because it is comparable to a Desktop 660 which is considered a good bang-for-the-buck graphic cards. If it isn't 200€ more on top of the 675MX I will take that option.
     
  12. macrumors 6502

    Joined:
    Jun 11, 2012
    #12
    For video editing is it going to be worth the upgrade from 675MX to 680MX or would you rarely see much of a difference between the two.
     
  13. macrumors 6502a

    Joined:
    Nov 20, 2010
    #13
    You would definately see a difference in high resolution gaming!
     
  14. macrumors 603

    Joined:
    Oct 14, 2008
    #14
    Both 675MX and 680MX are gaming GPUs. They are also useful if you are doing 3D design or similar - although in that case there probably won't be any difference between the two. If you want to play latest games at high settings at the native resolution - definitively go 680MX. But the 675MX is also pretty fast.

    Video is usually rendered on the CPU, so the GPU does not matter much.

    ----------

    I don't think that you will see much difference - it depends on whether your software uses GPU acceleration (and even then both cards would be probably similarly fast).
     
  15. macrumors 68030

    forty2j

    Joined:
    Jul 11, 2008
    Location:
    NJ
    #15
    Ahh.. very different questions.

    Although neither is optimized for rendering, both would do so very well. The 680MX would render a bit better - in this case primarily due to the VRAM and less the actual GPU performance. (Your use of the word rendering has been assuming you mean creating CGI Effects etc, not just splicing shots together.)

    For video editing (splicing shots), I don't expect it to make much difference. Serious video editing tends to be CPU limited, not GPU.
     
  16. macrumors 6502a

    Ice Dragon

    Joined:
    Jun 16, 2009
    #16
    I run smcfancontrol a lot so I would just use that to keep my iMac cool.
     
  17. thread starter macrumors 6502

    Joined:
    Jul 21, 2011
  18. macrumors 6502

    Joined:
    Oct 27, 2012
    #18
    WoW I did not know there was such a big gap between these two cards. It is like night and day. The 680 comes with pci express 3 where the 675 is using pci express 2. So the 680 requires the extra bandwidth? I wonder if the big difference in specification will be reflected in price. If it is only 100gbp then it has got to be worth it right?
     
  19. thread starter macrumors 6502

    Joined:
    Jul 21, 2011
    #19
    I've decided to stick with the stock GTX 675MX card & spend the money on the SSD Flash Storage instead.

    I rarely play games, and the most intensive activity I do is Adobe Premiere & After Effects, which will be more reliant on the i7 processor.
     
  20. 12dylan34, Nov 10, 2012
    Last edited: Nov 10, 2012

    macrumors 6502a

    Joined:
    Sep 3, 2009
    #20
    On CS6, both After Effects and Premiere can make quite effective use of GPU power, which can decrease preview and render times by a significant amount. Most plugins (the Trapcode Suite, Optical Flares and Element to name a few) in After Effects are sped up considerably with access to a good Nvidia GPU, not to mention the base programs themselves.

    After Effects

    Premiere Pro

    I would strongly suggest reconsidering if AE and Premiere are important to you. Neither the 675 nor the 680 are cited as "significant performance gains" by Adobe, but I wouldn't hesitate to future proof my machine for when Adobe writes better drivers.
     
  21. macrumors regular

    Joined:
    Oct 27, 2012
    Location:
    upstate NY
    #21
    Not too much, are you kidding? Since when does Apple stop overcharging?
     
  22. macrumors 68040

    MythicFrost

    Joined:
    Mar 11, 2009
    Location:
    Australia
    #22
    I'd say not always. But VRAM won't effect the frame rates at 1080p. It will only prevent bottlenecking at extremely high resolutions, or say at 1440p w/ high anti-aliasing.
     
  23. macrumors 6502

    boto

    Joined:
    Jun 4, 2012
    #23
    Might you reconsider the GTX 680MX? 2GB of VRAM is most likely going to benefit you in the long run if any software updates/features might make use of it.

    As for the SSD option, why not go with Fusion drive for higher storage capacity and nearly equal disk read/write speeds? If you are going to be purchasing the 512 or 768GB options then you can expect anywhere from $800-1300 based on the 13" rMBP configurations, opposed to $250 for a 1TB Fusion Drive or up to $550 for the 3TB option (1TB based on Mac Mini pricing, although it is a 5400RPM HDD). However, if your workflow requires pure flash storage for maximum performance than please disregard the aforementioned comments.

    The only thing I'm worrying about at this point is the pricing of the GTX 680MX. My intuition tells me Apple will charge $300-400, but I'm hoping for $200 at most.

    Oh, and the CPU upgrade is most likely going to cost $200 at most, accordingly to last year's model pricing for the i7.
     
  24. macrumors 6502a

    Ice Dragon

    Joined:
    Jun 16, 2009
    #24
    I mean if we are talking $200 or $300, fine. If it is $500 or more, forget it.

    You are already spending $2,000 for the iMac itself, you might as well get the top of the line video card as I see it.
     
  25. macrumors regular

    Joined:
    Oct 27, 2012
    Location:
    upstate NY
    #25
    I hope $200 is the price, but my intuition tells me that won't happen.
     

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