Dual video card question

Posted:
in Current Mac Hardware edited January 2014
I originally posted this in the MacBook Pro thread, but it got lost in a discussion of glossy screens.



I have a question about the dual video cards. In terms of outright effectiveness (when plugged in), is a 256 mb dual video card setup (like that on the new 2.4 GHz MacBook Pro) equivalent to a 256 mb single video card, or a 512 mb single video card?



For example, for the upcoming game Starcraft II, specifications are a 256 mb NVidia card as "minimum," and a 512 mb as "recommended." These ratings are for a single video card. Would the base MacBookPro with dual cards rated at 256 mb be equivalent to the "minimum" or "recommended"?

Comments

  • Reply 1 of 16
    in video cards ram size is just one of thing to look at.
  • Reply 2 of 16
    mitlovmitlov Posts: 130member
    Quote:
    Originally Posted by Joe_the_dragon View Post


    in video cards ram size is just one of thing to look at.



    Fair enough. Here's the question more specifically, then:



    Quote:

    Minimum Requirements

    GFX: GeForce 7/8 Series or Radeon 1000/2000 with 256 MB RAM



    Recommended Requirements

    GFX: GeForce 8000 or Radeon 2000 series with 512 MB RAM



    The new base MBP has:



    Quote:

    Graphics: NVIDIA GeForce 9600M GT graphics processor; and NVIDIA GeForce 9400M graphics processor with 256MB of DDR3 SDRAM shared with main memory



    Graphics memory: 256MB GDDR3



    Is this equivalent to the "minimum requirements," or above it? I am not as computer literate as many here; my apologies if this question is stupid or obvious.
  • Reply 3 of 16
    Quote:
    Originally Posted by Mitlov View Post


    Fair enough. Here's the question more specifically, then:







    The new base MBP has:







    Is this equivalent to the "minimum requirements," or above it? I am not as computer literate as many here; my apologies if this question is stupid or obvious.



    The 9600M GT has 256MB of GDDR3. That's it. Even if Apple is using SLI for a performance boost instead of just power savings (which I really doubt), the memory amount is not cumulative.



    It isn't terribly important, either. With only a 128-bit memory bus, the 9600M GT probably can't use 512MB of memory, anyway.
  • Reply 4 of 16
    Also, it is NOT dual video cards. It is integrated graphics, plus a discrete GPU (a video "card"), with the ability to shut off the discrete GPU when you want to save power. Or turn on the discrete GPU when you need more graphics power, if you want to think of it that way.
  • Reply 5 of 16
    mitlovmitlov Posts: 130member
    Thank you for the explanation, FuturePastNow. That helps a lot.
  • Reply 6 of 16
    Only thing is to switch from the two graphics processor, you will need to reboot, which is a pain.
  • Reply 7 of 16
    sc_marktsc_markt Posts: 1,402member
    Quote:
    Originally Posted by FuturePastNow View Post


    Also, it is NOT dual video cards. It is integrated graphics, plus a discrete GPU (a video "card"), with the ability to shut off the discrete GPU when you want to save power. Or turn on the discrete GPU when you need more graphics power, if you want to think of it that way.



    So is the discrete GPU in these new MBP's equal to the same model real video card? Or are we getting less video processing power with these on board integrated discrete GPU's?
  • Reply 8 of 16
    Quote:
    Originally Posted by sc_markt View Post


    So is the discrete GPU in these new MBP's equal to the same model real video card? Or are we getting less video processing power with these on board integrated discrete GPU's?



    The 9600M GT can be comparable to the desktop version of the 9500 GT. This is, of course better than the 8600M GT that Apple offered in the last generation MBPs. Still it is on a 128 bit bus which makes it slower than a 256 bit bus which would allow it to perform and utilize all VRAM effectively.
  • Reply 9 of 16
    Quote:
    Originally Posted by itisme1760 View Post


    Only thing is to switch from the two graphics processor, you will need to reboot, which is a pain.



    Can you provide a source for that info?



    - Jasen.
  • Reply 10 of 16
    Quote:
    Originally Posted by jasenj1 View Post


    Can you provide a source for that info?



    - Jasen.



    http://www.appleinsider.com/articles...ook_event.html



    Quote:

    While Apple's new MacBook Pro potentially delivers longer battery life by switching to integrated video instead of its more powerful discrete chipset, Apple notes in a support document that users can't just flick a switch and trigger the new mode.



    Instead, changing energy preferences to favor either better battery life (with the GeForce 9400M) or faster performance (with the 9600M GT) prompts the notebook's owner to log out and back in for the change to take effect. It's not known whether disconnecting or reattaching power makes the switch automatically.



    I meant log out, not reboot.
  • Reply 11 of 16
    sc_marktsc_markt Posts: 1,402member
    Quote:
    Originally Posted by itisme1760 View Post


    The 9600M GT can be comparable to the desktop version of the 9500 GT. This is, of course better than the 8600M GT that Apple offered in the last generation MBPs. Still it is on a 128 bit bus which makes it slower than a 256 bit bus which would allow it to perform and utilize all VRAM effectively.



    Thanks!



    While I'm asking questions, here are a few more.



    1) Can you plug in firewire 400 in a firewire 800 port with an adapter?

    2) Do express/34 cards come with firewire 400 ports?

    3) Does anybody here use their express/34 ports for anything?
  • Reply 12 of 16
    Quote:
    Originally Posted by sc_markt View Post


    Thanks!



    While I'm asking questions, here are a few more.



    1) Can you plug in firewire 400 in a firewire 800 port with an adapter?

    2) Do express/34 cards come with firewire 400 ports?

    3) Does anybody here use their express/34 ports for anything?



    1) Yes, Apple provides this for ~$30

    2) Yes, http://www.sonnettech.com/product/fw...esscard34.html

    3) Don't know, I don't.
  • Reply 13 of 16
    Quote:
    Originally Posted by sc_markt View Post


    So is the discrete GPU in these new MBP's equal to the same model real video card? Or are we getting less video processing power with these on board integrated discrete GPU's?



    The 9600M GT is half as powerful as a desktop 9600GT card. They're not equivalent, if that is what you're asking. You'll get the full power of the 9600M, but it is only a little bit more powerful than an 8600M.
  • Reply 14 of 16
    jasenj1jasenj1 Posts: 923member
    Quote:
    Originally Posted by itisme1760 View Post


    http://www.appleinsider.com/articles...ook_event.html



    I meant log out, not reboot.



    Thanks. Logging out is definitely not optimal. I usually unplug my MBP from my desktop set up, close the lid, take it wherever, flip it open, and keep on working. Having to close all apps and log out and back in would definitely be a bit cumbersome.



    - Jasen.
  • Reply 15 of 16
    programmerprogrammer Posts: 3,458member
    Quote:
    Originally Posted by itisme1760 View Post


    Still it is on a 128 bit bus which makes it slower than a 256 bit bus which would allow it to perform and utilize all VRAM effectively.



    Note that having half the width of the bus (i.e. 128 bit vs. 256 bit) does not, in and of itself, have any implications on the amount of addressable VRAM. It can still use it all, its just that memory access is half as fast if all other things are equal. You also need to look at the bus/VRAM clock rate between the two -- if they doubled or double-pumped the clock rate on the 128 bit bus, it would perform as well as the 256 bit bus. I haven't looked at the specs on these things, so I don't know the answers to these questions.
  • Reply 16 of 16
    Quote:
    Originally Posted by Programmer View Post


    Note that having half the width of the bus (i.e. 128 bit vs. 256 bit) does not, in and of itself, have any implications on the amount of addressable VRAM. It can still use it all, its just that memory access is half as fast if all other things are equal. You also need to look at the bus/VRAM clock rate between the two -- if they doubled or double-pumped the clock rate on the 128 bit bus, it would perform as well as the 256 bit bus. I haven't looked at the specs on these things, so I don't know the answers to these questions.





    Too bad they can't because of thermal issues.
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