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NVIDIA Responds To GTX 970 Memory Bug

Vigile writes Over the past week or so, owners of the GeForce GTX 970 have found several instances where the GPU was unable or unwilling to address memory capacities over 3.5GB despite having 4GB of on-board frame buffer. Specific benchmarks were written to demonstrate the issue and users even found ways to configure games to utilize more than 3.5GB of memory using DSR and high levels of MSAA. While the GTX 980 can access 4GB of its memory, the GTX 970 appeared to be less likely to do so and would see a dramatic performance hit when it did. NVIDIA responded today saying that the GTX 970 has "fewer crossbar resources to the memory system" as a result of disabled groups of cores called SMMs. NVIDIA states that "to optimally manage memory traffic in this configuration, we segment graphics memory into a 3.5GB section and a 0.5GB section" and that the GPU has "higher priority" to the larger pool. The question that remains is should this affect gamers' view of the GTX 970? If performance metrics already take the different memory configuration into account, then I don't see the GTX 970 declining in popularity.

28 of 145 comments (clear)

  1. Hey! I've been gypped! by Virtucon · · Score: 2

    My Ferrari only goes 210 MPH but they said it would go 217!

    --
    Harrison's Postulate - "For every action there is an equal and opposite criticism"
  2. False Advertising by Anonymous Coward · · Score: 3, Insightful

    I'm just going to come out and say that to advertise the card with 4GB, but then disable any amount of it, is false advertising. Sure, most games can't actually hit 4GB since most games are still brain-dead 32-bit applications that can't access more than 4GB of any memory.

    But this is a sign of things to come. Where the next generation sub-20nm GPU's will be advertised with RAM amounts and supposed to have 2-3X the processing power, but part of the GPU will be competely unusable because the operating system or software being used isn't 64-bit aware.

    1. Re:False Advertising by Gravis+Zero · · Score: 3, Informative

      I'm just going to come out and say that to advertise the card with 4GB, but then disable any amount of it, is false advertising.

      i agree. however in this case, all 4 Gigabytes are accessible, they simply aren't accessible at the same speed. the final 500MB is "slow" to access but it's still there and you can still access it.

      --
      Anons need not reply. Questions end with a question mark.
    2. Re:False Advertising by Solandri · · Score: 3, Informative

      I'm just going to come out and say that to advertise the card with 4GB, but then disable any amount of it, is false advertising. Sure, most games can't actually hit 4GB since most games are still brain-dead 32-bit applications that can't access more than 4GB of any memory.

      But this is a sign of things to come. Where the next generation sub-20nm GPU's will be advertised with RAM amounts and supposed to have 2-3X the processing power, but part of the GPU will be competely unusable because the operating system or software being used isn't 64-bit aware.

      VRAM has nothing to do with system RAM. VRAM is special memory used by the dGPU, and only the dGPU, for storing framebuffers, textures, models, and other data needed to draw a 3D scene. It's faster than system RAM (GDDR5 is typical, vs DDR3 for regular RAM), and positioning it closer to the GPU reduces latency due to the speed of light (which travels only 10 cm in a single 3 GHz cycle). So the 32- or 64-bitness of the OS and apps has nothing to do with the video card's ability to access 4GB or more of VRAM.

      In particular, the 970 GTX has a 256-bit memory bus. The speed constraint of having to retrieve data from VRAM one 32-bit (float) or 64-bit (double) "chunk" at a time became a bottleneck long before the inability to address that VRAM as a flat memory space. So mid- and high-end video cards are designed to retrieve multiple "chunks" of data from VRAM simultaneously. You have to drop all the way down to the GT 730 before you get to video cards using a 64-bit memory bus.

    3. Re:False Advertising by Smauler · · Score: 2

      Anyone who buys a graphics card based on how much memory it has is going to be disappointed. It's _way_ cheaper to chuck mediocre cards out with lots of RAM than it is to produce good cards.

      Benchmarks, benchmarks, benchmarks, people. Don't look at what it is called, or how much memory it has, look at what it _does_. I'm talking about real world gaming benchmarks here, not 3dmark or anything. And yes, they do manipulate these a bit, but it's much, much harder to manipulate them.

      All that being said, this is a shitty move by nvidia.

  3. Re:Hey! I've been gypped! by Anonymous Coward · · Score: 2

    It's true though, they lied. Try to do the same when paying a bill (pay 210$ when it says 217$), you'll see how these companies will send their legions of lawyers after you just to get that little 7$.

  4. Well, it's more like they said... by Ecuador · · Score: 2

    That it will go 200 MPH like the equivalent model from other brands like Lamborghini etc but it turns out it goes 175, i.e. slower than those. Sure, you would not have realized it until you actually found a road good enough to test over 175 MPH (if you ever did) and otherwise the car feels good and accelerates as expected, but max speed is something that some people care about especially when comparing one sports car with the other. The excuse is sort of like "yeah, we put in an engine that would theoretically handle 200 MPH so that is what we list, but we sort of skimped on the transmission system on this less high end model so we had to put a limiter at 175 MPH since the transmission cannot address more speed...". If they had said 3.5GB addressable from the start, nobody would have minded except the 5 people who really wanted those 4GB that other cards might have, so it is sort of a poor decision to not mention it from the start...

    --
    Violence is the last refuge of the incompetent. Polar Scope Align for iOS
    1. Re:Well, it's more like they said... by Immerman · · Score: 2

      If the advertising said X was a feature, and that claim was a factor in me buying it for the asked-for price, then I paid for that feature. All else is irrelevant.

      --
      --- Most topics have many sides worth arguing, allow me to take one opposite you.
  5. Not a bug. by Anonymous Coward · · Score: 4, Insightful

    It isn't a but. It's a lie.

    These cards are advertised and sold as having 4gb of DDR5, but actually only have 3.5gb and then 0.5gb of slower stuff. When you are buying high end cards to pump a lot of pixels, all of this is consumed, meaning you will hit unnecessary performance limitations. Especially when moving to an SLI setup.

    This is shady bullshit. This isn't a case of "You screwed me out of one percent and I'm going to whine about it". This is the case of people spending a thousand bucks for a certain level of performance and compatibility that they have come to expect form the product and, instead, finding themselves penalized for being power users.

    1. Re:Not a bug. by SpankiMonki · · Score: 2

      These cards are advertised and sold as having 4gb of DDR5, but actually only have 3.5gb and then 0.5gb of slower stuff.

      I don't think so. The only difference between a 970 and a 980 is that nVidia gimps the 970's GPU by 2 SMMs, which is 1/8 less than a 980. Strangely, 3.5GB is also 1/8 less than 4GB.

  6. Re:Hey! I've been gypped! by Richard_at_work · · Score: 4, Insightful

    Tell us where they lied - the card has 4GB of memory in one bank, its logically separated out internally when used by the cards processor. But it still has 4GB of memory.

  7. Re: Hey! I've been gypped! by O('_')O_Bush · · Score: 2

    Except, to get the analogy right, it would be important to consider that: 1. 0.5 GB is only 12.5% of the total pool (not 75% as in your analogy), and 2. Probably 99.9% of users don't have applications or hardware to use more than half of that VRAM anyways, unlike 100% having a need for more braking performance, as with your analogy.

    --
    while(1) attack(People.Sandy);
  8. Re:This reminds me... by pushing-robot · · Score: 5, Informative

    You're describing 'TurboCache' (a marketing name if ever there was one).

    It wasn't a secret, it was only on very low end cards, and ATI was already doing the same with 'HyperMemory'. Intel, for their part, was exclusively using system RAM at the time (and largely still is).

    So what graphics *have* you been buying for the last decade?

    --
    How can I believe you when you tell me what I don't want to hear?
  9. Re:Hey! I've been gypped! by Rick+Zeman · · Score: 5, Funny

    Tell us where they lied - the card has 4GB of memory in one bank, its logically separated out internally when used by the cards processor. But it still has 4GB of memory.

    They just need to run himem.sys with the right parameters.....

  10. Wasn't from an engineer.... by beheaderaswp · · Score: 3, Insightful

    Looks to me like the marketing department at nVidia is running the show.

    An engineer would never hide this distinction.

    I'd be unhappy if I found out my 980 had this flaw. Can't blame the consumer at all.

    Sorry guys... complain away you deserve it.

    --
    Another consultant who stuck it out.

    "We are the Priests, of the Temples of Syrinx..."
  11. Re: Hey! I've been gypped! by PopeRatzo · · Score: 2

    . Probably 99.9% of users don't have applications or hardware to use more than half of that VRAM anyways

    Sure they do. People who are buying the 970 are either gamers or dopey bitcoin miners, and the top tier (and most of the middle-tier) of new games will use 4gig VRAM. Who knows about the bitcoin mining because that's all nonsense anyway. But I'll bet their little programs that they run using $1 of electricity to get 50 cents in bitcoins use every bit of that 4gig VRAM. Because they've got nothing but time to deal with bitcoin mining and GPU performance since they dropped out of grad school and now dad keeps insisting that they be looking for work but how can they do that when they're mining bitcoins goddamnit, which is the future of money and then they'll never need a job because they'll be the ones with all the money and dad's Roth IRA is going to be worthless, watch and see. And if they could just get they're hands on another $1500 (you know dad probably has it), they could really get this bitcoin rig humming and then they'd be spending $1 of electricity to mine 75 cents worth of bitcoins.

    Gamers on the other hand (like me) paid for 4gig of VRAM to get more p's and more frames-per-secondses, and by god, we deserve to get 4 gig of VRAM.

    --
    You are welcome on my lawn.
  12. Re: Hey! I've been gypped! by Bender+Unit+22 · · Score: 2

    I have 4gb in my IMac (although just a 720gtxm) . I am not a gamer but Final Cut Pro uses the gpu when analyzing or altering video content.

  13. Re:Hey! I've been gypped! by ArcadeMan · · Score: 4, Funny

    I you want real shivers, don't forget to use EMM386 and to LH your CD-ROM and mouse drivers.

  14. Re:Hey! I've been gypped! by ArcadeMan · · Score: 3, Funny

    Yes, you have been lied to. Windows is in fact a 32 bit extension and a graphical shell for a 16 bit patch to an 8 bit operating system originally coded for a 4 bit microprossessor, written by a 2 bit company that can't stand 1 bit of competition.

  15. Re:Thank god I bought a 980. by ArcadeMan · · Score: 2

    I also avoided the same fate. I bought a fanless Zotac GT630 1GB.

  16. It also doesn't really matter by Sycraft-fu · · Score: 4, Insightful

    Thing thing is if you go and look at benchmarks of the cards in actual games, you find out the 970 wrecks shit, particularly given its price point. The 980 is an overpriced luxury (I say this as a 980 owner) because the 970 gets nearly the same performance for like half the price. The difference with its memory controller just doesn't seem to matter in actual games out there on the market.

    And that's the real thing here the the spec head forget: You buy these to run actual software. If it does well on all actual software, then who gives a shit about the details?

    1. Re:It also doesn't really matter by Kjella · · Score: 2

      Whether the GTX 970 has 3.5 or 4 GB effective it's still more than a standard GTX 780 Ti with 3 GB, so I'm guessing you have to run some rather extreme resolutions and AA modes to see a practical difference. In fact the latter will generally beat a 970 whether single vs single or SLI vs SLI at UHD (3840x2160) resolutions.

      What I do know is that my 2x970 totally trashes a single GTX 980 at a 20% price premium as they do have 2x13/16 = 26/16 the shaders, both cards shut down the fans at idle so it's extremely quiet and even at full tilt both cards together pull just 2x145W = 290W. I'm kinda surprised nobody's done a single card version yet since it's still under the 300W ATX limit.

      It runs games at 3840x2160 on a Samsung UD590 beautifully, even though it's a 1ms TN panel it's not for twitch gaming as it's 60 Hz on DisplayPort with no fancy sync options and 25ms input lag but it looks extremely good. And at monitor distances you can definitively see the upgrade over 1080p while the TV benefits are more dubious. There are better setups, but for being such a high-end system the price/performance was extremely good.

      --
      Live today, because you never know what tomorrow brings
  17. Car analogy by ruiner13 · · Score: 3, Interesting

    It is the same as selling a car saying it has a 20 gallon gas capacity, then finding out that the tank itself is 15 gallons and there are 5 one gallon gas cans in the trunk. Yes, there's 20 gallons. Yes, it is all usable. However using the last 5 gallons is slow because you have to stop the car and keep adding it to the tank. Sure, you're getting 20 gallons, but it can't all be used at the same time.

    --

    today is spelling optional day.

  18. Re:Hey! I've been gypped! by drinkypoo · · Score: 2

    QEMM forever! Oh, what's this, memmaker? hmmmmm

    --
    "You're right," Fisheye says. "I should have set it on 'whip' or 'chop.'"
  19. Re:Hey! I've been gypped! by wierd_w · · Score: 3, Informative

    Silly person!

    Use UMBPCI instead of EMM386, and use CTMOUSE for the mouse driver.

    (assuming your modern system still knows how to play right in real mode anyway. Many modern chipsets have problems with ISA style DMAs, which makes using the hardware UMBs free with UMBPCI can have unpredictable results. For such systems, you are stuck with EMM386 doing protected mode memory reassignments, and gobbling down a big chunk of conventional. Blech.)

    Really, there are much better memory managers that came about since the DOS days (FreeDOS is still a living project for devices that simply must run DOS. Industrial vinyl cutters and the like come to mind), and you can reasonably get over 568k conventional free with little hassle.

  20. Re:Hey! I've been gypped! by ArcadeMan · · Score: 3, Funny

    Well thank you very much. I'll be here all week!

  21. Re:Hey! I've been gypped! by hairyfeet · · Score: 2

    Because it can't actually USE all the RAM? Its like saying "Windows XP can have up to 4GB of RAM" which while TECHNICALLY true is bullshit because of the way 32bit Windows works the max you'll ever be able to get the OS to use is around 3.5GB, with most systems only hitting around 3.2GB-3.4GB.

    If they were selling this as a 3.5GB card? I'd say fine and dandy, card makers often will disable parts that either don't work or to have different tiers at different price points but in this case they are advertising and selling it as a 4GB card when its really only a 3.5GB thanks to the way they gimped the chip.

    --
    ACs don't waste your time replying, your posts are never seen by me.
  22. Re:Hey! I've been gypped! by wierd_w · · Score: 4, Insightful

    I dont know? I remember all kinds of things.

    I DO have a large collection of old retro DOS games, some of which are still quite fun to play, but which dont run worth SHIT on WINE or modern windows. (and cruising inside dosbox just doesn't feel the same. MoSlo and real hardware feel like the genuine experience.)

    My inability to forget legacy shit sometimes pays off, when I come in contact with a poor IT wage slave who has to maintain legacy CNC equipment. (Sometimes phone equipment too, but mostly CNC equipment) Things like 2D vinyl cutters, old PCB milling/masking machines, etc. Those things cost millions of dollars when new, and despite being ancient beyond words inside by modern standards, the owners rarely consider "buying a new one" an acceptable solution, as long as said expensive legacy devices can be coaxed into continuing to make product. Typically, these devices simply cannot be upgraded to a more modern OS, for multitudinous reasons. The most commonplace one is that there simply arent any drivers for the custom PCI (or even ISA!) cards inside them, and the drivers that do exist require realmode level control over the hardware to work (Or the control software is so poorly written that it can't work on anything newer, etc.).

    Sometime last year, the topic of how to reduce the need for re-imaging win9X installations came up here on slashdot. (I forget the story.. does not matter) A poster was in the undesirable position of having to maintain such a legacy device, and my inability to forget legacy shit paid off for him. I told him that he could basically make his legacy devices damned near maintenance free by using syslinux as the bootloader with an ext2 partition holding a small (512mb or so) disk image, and using memdisk. System acts goofy? Just reboot it. Fresh, clean image each and every time. Because the actual HDD is formatted with an EXT flavor OS, the win9x running does not see it or use it for anything. The actual HDD never gets written to. Switching out an aging IDE disk with a CF->IDE adapter, this works out just fine. The flash is never written to, just read from, even when windows is running.

    He was having problems where he would have to re-image his CF cards every few months because of how intrinsically shitty and unstable win9x was. He was VERY interested in running win9x from a ramdisk. I never heard back, but I hope it worked out for him.

    As for why I can't seem to ever forget? Who knows. I'm just unlucky maybe?

    I can shit out a config.sys and autoexec.bat right from the dos prompt, straight from memory even to this day.