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Graphics Memory Sizes Compared: How Much Is Enough?

EconolineCrush writes "Trying to decide between whether or not to get a 64MB graphics card, or spring for that 128MB version? Hit up this article, which explores the performance of ATI and NVIDIA-based cards with 64 and 128MB of memory, before swiping your credit card. Not so long ago 32MB was the top end for graphics memory on consumer video cards, but now even budget cards are available with 128MB. 128MB might seem excessive now, but a year from now 64MB cards might just be obsolete."

20 of 306 comments (clear)

  1. Bah... by RQuinn · · Score: 4, Funny

    a year from now 64MB cards might just be obsolete

    Bah. Next thing you'll be trying to tell me my Voodoo 3 2000 PCI is obsolete!

    1. Re:Bah... by Ravensfire · · Score: 3, Funny

      Pssst - it's obsolete!

      --
      "But we decide which is right, and which is an illusion"
  2. removable RAM? by littlerubberfeet · · Score: 5, Interesting

    this might be offtopic, but why can't the RAM on graphics cards be modular, like the stuff we stick in computers? Is it a card manufacture conspiracy? a different type of RAM? I would be willing to buy a high end Graphics card if I could eventually stick 256, or 384 MB on the card.

    --
    Sig (appended to the end of comments you post, 120 chars)
    1. Re:removable RAM? by Milican · · Score: 5, Interesting

      By soldering the RAM directly to the board there is a better connection which allows them to run the chips faster. If you add a connector then you add a capacitive load and thus you have to slow down the memory. Thats not to say modular RAM could not be incorporated down the line, but for the latest and greatest its better and cheaper to solder the stuff right on the PCB (printed circuit board).

      JOhn

    2. Re:removable RAM? by hike2 · · Score: 3, Interesting

      In the case of NVIDIA the "value-added resellers" add their own high-speed memory as in the case of Leadtek. If they were to make the memory modular they could not charge and extra 50-100 bucks over the comptetition just so that you can gloat at your extra .5% gain over you buddies exact chipset.

      --
      Fourty-two!
    3. Re:removable RAM? by RandomCoil · · Score: 3, Funny

      Nice work Beavis :), you just upped the US's trade deficit as hundreds of overclockers destroy their motherboards attempting to solder in their RAM modules.

      No doubt you'll be receiving an extra bonus from the Taiwanese motherboard manufacturers this month. Of course I suppose that assumes they're able to recognize solder drips and scorch marks as good reasons to assume the board was not received DOA...

      (Yes, I realize there are overclockers all over the world -- I apologize in advance for my horribly US-centric post... geez...)

    4. Re:removable RAM? by John_Booty · · Score: 5, Informative

      this might be offtopic, but why can't the RAM on graphics cards be modular, like the stuff we stick in computers?

      Another reason in addition to the ones posted by other users... when are you going to upgrade the memory on your graphics card? Perhaps 12 months after you bought it? Two years?

      --If you're going to stay close the cutting edge in PC graphics, you'd be buying a new card at the point. Considering the pace at which PC graphics card technology increases, your card would be fairly dated by that point anyway and you'd be looking at another one.

      --If you were going to buy the extra video memory fairly soon after purchasing your card when it's still bleeding-edge, why not buy a card with that much RAM in the first place?

      Of course, other posters have noted lots of good reasons as well such as the profits made by board/chip manufacturers on the extra RAM, physical RAM connection issues, etc, etc.

      --

      OtakuBooty.com: Smart, funny, sexy nerds.
    5. Re:removable RAM? by Milican · · Score: 3, Informative

      OK, well 2pF may not seem like alot and in most cases its not. However, what you are forgetting is the scale we are working at here. I tried to lookup the exact memory module for a GeForce card, but I couldn't so I just went to Micron's site and looked up their spec on their 256Mb DDR333 SDRAM. If you will look on page six you will see the capacitance ratings for each signal line are as low as 0.5pF for three of the signal lines and max out at 4.0pF for the I/O (data) lines on the memory module. So lets look at the 2pF number again. By adding a connector you increase your input capacitance by 400% in some cases and 50% in the best case scenario. This is very bad and will directly impact how much memory can be put on one bus and how fast the memory can be timed. The more input capacitance you have on a line the harder the output buffers of the graphics chip (or memory controller) have to work. More input capacitance directly affects how fast you can get that nice little square wave signal to look nice enough to be registered on the other side. The more input capacitance the longer it takes, and this is all very relevant at the speeds we are talking about here. Also, FYI other factors for not using a connector include trace length. By adding modules you are increasing trace length by a large amount (relatively speaking of course). This also adds input capacitance.

      So now you are probably asking. How much capacitance can a typical graphics chip or processor drive? Well I tried to find the datasheet on nVidia's website for their GeForce chips, but didn't turn up a thing. So I went to Intel's site and looked up the datasheet for their 845G chipset with integrated graphics. If you look on page 525 you will see that the output drive for the Intel chip is 12pF. So now you can probably see the problem. Assuming all we drove were memory modules directly from the 845G (which we wouldn't in real life) we could put just two to three 256Mb (32MB) modules on board without connectors. If we put the Molex connector you specified in between that number changes from 1 - 2 chips. In real life we would put a nice buffer in between that has a stronger output drive in between the 845G and the memory. Like TI's 24-Bit to 48-Bit Registered Buffer. That sucker has a 30pF drive and each buffer could easily drive 6 - 7 modules for a total of 256MB of RAM without the connector. Add a connector and this number deindles to 4 - 5. Anyway, I'm sure you get the point. At this scale even a 2pF connector makes a big difference.

      However, after saying all that I should mention that I do not believe that these electrical considerations are the main or only reason the cards are not expandable. I think alot of it has to do with demand. Very few people are gonna upgrade their video card with more memory. I don't know any Matrox Millenium owners, including me, that upgraded their memory on their video cards. Because the economies of scale for a specialized memory make them much more expensive to produce than consumers like myself are willing to pay. In adition, by the time I am gonna upgrade a cards memory I can probably buy a brand new one with that amount of memory for the price of the piddly module ;)

      JOhn

  3. 64Meg Card obsolete? by gurnb · · Score: 5, Insightful

    How can you say that a 64Meg Video card may be obsolete in a year!?

    If a piece of hardware is doing what you need it to do, then it is not obsolete. Not every plays/needs/wants the latest UT2003/Doom3 game.

    --
    "This must be a Thursday, I never could get the hang of Thursdays."
  4. enough is when winamp truly rivals LSD by Anonymous Coward · · Score: 3, Funny

    Maybe with enough RAM, processor speed and plasma displays I could create a $50,000 virtual reality room where winamp visuals would rival a $3.00 hit of LSD.

    Wouldn't that be cool. You could make your freakin trip end when you needed it to. Game Over Man. Legal too.

  5. Obsolete? So what? by iiioxx · · Score: 5, Insightful

    "...but a year from now 64MB cards might just be obsolete."

    So? A year from now, 128MB might be a low-end card, too. So in a year, buy a new card. Don't invest in tomorrow's technology today at a premium, when you can get it tomorrow at a discount. That's why smart buyers invest in modular components. When your hardware gets outdated, pluck and chuck.

    I never invest in the top-end. I buy in the middle ground. Why? Because components drop from high-end to mid-range very quickly, but then stay there a long time before obsolescing to the low-end (or dead-end). And when a product drops from the high-end to the middle ground, the pricetag typically gets cut in half.

  6. Getting an nvidia? 128 or 64? Read this... by Rahga · · Score: 5, Informative

    Here's something you should consider before buying a 128 MB GeForce Ti-series card. There are four choices you can make right now:

    Ti-4600: Highest price, best features, 10.4 GB/s memory bandwidth, 650 MHz memory clock
    Ti-4400: High price, excellent features, 8.8 GB/s memory bandwidth, 550 MHz memory clock
    Ti-4200 (1): Decent price, great features, will handle BF1942 and UT2003, 64 MB limit, 8 GB/s memory bandwidth, 500 MHz Memory clock
    Ti-4200 (2): High price, great features, slowest out of all 4 thanks to memory speeds, will handle BF1942 and UT2003, 128 MB limit, 7.1 GB/s memory bandwidth, 444 MHz memory clock.

    Basicly, on the 4200's, if you go for double the memory for almost double the price, you will see a performance hit.

    After my research (urged on by PNY's box), I decided that by the time I need 128 Mhz, I'll also want the features of a chip beyond the current Nvidia line.

    Of course, if you want anything that performs beyond the 4200, then why bother reading anything here in slashdot? You're getting at least 128 MB on your card ;) .....

    So, this weekend, I found a 64 MB Ti 4200 for $129, and it printed out a $30 rebate at the counter. Happy day, indeed. I spent the rest of the weekend playing OpenGL-boosted Doom and Hexen.

    BTW, if you are completely out of the know, but love gaming, do not but the MX series of cards. They are not for you.

  7. texture memory by phorm · · Score: 3, Insightful

    AGP will let you run the textures from your video card off of system RAM, but there is still a speed loss involved in this. More RAM is of course nicer for newer games. Older games, it doesn't mean squat. No games, squat. Games without 3d, squat. (no I'm not counting those who use the video card for system memory).

    However, if you intend to play Q3 or whatever enough at superhighres, ultracolordepth, whateverwhatever, then you may want more Video RAM. Crank down the texture detail a little bit and you don't need as much, I'm sure the game is just as fun.

    AGP, fast video cards and video RAM are all about games. But when you can buy a whole PS2 for the cost of an expensive video card, it makes you think a bit.

    With my old 15" 1024x1024maxres monitor it doesn't matter much anyhow - phorm

  8. Re:Ridiculous for most users by geekoid · · Score: 3, Funny

    You don't. The article is not meant for you. Move along.

    --
    The Kruger Dunning explains most post on /. http://en.wikipedia.org/wiki/Dunning%E2%80%93Kruger_effect
  9. I'm not trying to brag or anything, but.. by kaoshin · · Score: 3, Informative

    My 1MB trident SVGA card works just fine. Enlightenment looks great in 800x600x16bit,
    and I play alpha centauri, starcraft, freeciv, etc. And I have been using it day and night since around 1993 without it melting, and with no noisy cooling fans. Considering it cost me one buck, I think that it is not a bad bargain.

  10. Re:What are you doing with it? by andycat · · Score: 5, Interesting
    At work the two machines I use regularly for interactive walkthroughs of large environments (10-100 million triangles) have 64MB and 128MB of texture memory, respectively. I am constantly running up against the 64MB limit and I'm fast approaching the 128MB one. Here's how it breaks down:

    Frame, depth, and stencil buffer: 1024x1024x(32 bits + 32 bits + 8 bits) = 9 megabytes

    9 megabytes so far. No problem. Double that when I push the resolution up to 1600x1200 for demos, but we'll ignore that for the moment. Now, the model I'm using has 19MB of surface texture, so we're up to 28MB. The system I'm running on this poor hypothetical card uses 512x512 textures to replace distant geometry. Each one takes up 768K of memory and I've generally got a working set of between 40 and 60 textures. There's another 30-45MB, so total usage is somewhere between 58 and 73MB. Add in shadow maps and we lose another 20 or 30MB. The 64MB card is now swapping to AGP memory. The 128MB card is filling fast. It's adequate for the current generation of the system I'm running, but before I can write the next couple versions I'm going to have to implement some serious resident-texture-set cache management.

    Now, you can certainly argue that this is an atypical application. You would be quite correct. However, I do need that much video memory and I do use it. Yes, it's massive overkill if you want to play Quake, Unreal, whatever, but once you start looking into more exotic applications it's easy to get into situations where you can use arbitrary amounts of texture RAM. Real-time shading can get you there in a hurry, too, once you start using textures as lookup tables for expensive-to-compute functions (e.g. light fields or factorized BRDFs) or caching the framebuffer for later re-use.

    So yes, 90% of the programs 90% of users will run will currently fit neatly in 64MB of video memory, but there definitely exist systems that require more than that.

  11. Re:Obsolete? So what? by kaladorn · · Score: 3, Funny

    Don't invest in tomorrow's technology today at a premium, when you can get it tomorrow at a discount. That's why smart buyers invest in modular components. When your hardware gets outdated, pluck and chuck.

    No! No! No!

    Please DO invest today in the top-end graphics cards! Spend two to three hundred $ buying the best cards on the market! (Or more!)

    You see, unlike the parent poster, I think this is a positively brilliant plan for each and every one of you in the high-end gaming crowd!

    Look at the benefits: State of the art technology, frame rates so fast that subliminal advertising is practical, bitBLTs that could move your entire DNA encoding in one transfer, and colour depth that makes the games so close to real life you never have to leave your chaise-lounge and encounter the real world!

    And as a nice bonus for those of us in the category of the less driven to best-of-the-best-damn-the-cost, there is this:

    As all of the high end gamers drive the market up, some really decent hardware becomes really cost-effective and affordable for the rest of us!

    So yes, Please Please Please DO buy the BEST and Most Expensive! Drive the market as hard as it can be driven! The mild and meek will quietly thank you and buy really nice (but obviously outdated) products for a bargain basement price!

    Ooops.... forgot to tag the whole post <SARCASM>

    --
    -- Mal: "Well they tell you: never hit a man with a closed fist. But it is, on occasion, hilarious."
  12. It's mostly texture memory by ikekrull · · Score: 5, Informative

    These card use up to about 4MB - more like 2MB or less for 16-bit modes, for the framebuffer, and the rest is used solely for storing textures.

    If you do not use OpenGL/Direct3D, then any RAM above, say 8MB (you may be doing dual or triple-head at 1600x1200 32bit or more), is completely useless.

    The extra bandwith on the cards is also useless, as only 3D operations are accelerated across the super-fast busses built into these cards.

    Everything else, including 2D blits in the majority of available OpenGL/Direct3D drivers are handled by the host CPU and involve reading from system RAM and passing that data across the AGP bus.

    I am not aware of many (any?) games that can take advantage of more than 64MB of texture RAM, and while games that *may* take advantage of >64MB are on the horizon, the big news for games is vertex/pixel shaders, rather than the ability to texture map hundreds of megabytes of pixel data per frame.

    There are applications that will benefit from the availablity of 128MB or more texture RAM, but these are typically custom-written scientific visualisation apps, or conceivably you could use 128MB of textures to do realtime previews in your lightwave/3DS Max/Maya/Blender scenes.

    However, the actual utility of this RAM for most desktop users and even gamers is rather questionable. I don't doubt that the Radeon 9700 and the NVidia Ti4600 are fast cards, but they still rely heavily on the host CPU to achieve their stellar performance, as opposed to some of the professional cards which provide much more capable geometry engines and accelerate practically all of the openGL pipeline, as opposed to the consumer cards which are focussed mostly on texturing and fillrate optimization, ideal form games but not necessarily optimal for other forms of 3D activity.

    That being said, the pace of development from Intel and AMD have made it more difficult to justify using dedicated hardware for these seteps, as a 2GHz Athlon will probably out-light-and-transform dedicated OpenGL hardware, which is much more costly and low-volume to produce.

    The SGI O2 is a good axample of a machine that simply uses system memory to store textures, and while the SGI's graphics system is not in the same class as some of the more modern 3D boards from NVidia and 3DLabs, it is certainly sufficient to do impressive texture-mapping demos. This is really not an option on the current x86 architectures, but is a useful example of the 'other' way to handle texture memory, as it allows the user of the system to make maximum use of the resources available - i.e. when 3D graphics are not used, the 'texture memory' is available to the apps, and vice-versa.

    I think it is amazing that we now have consumer cards that contain more texture memory than was typically available as system RAM in a mid-range 3D workstation a few years ago, but the unfortunate thing is that very, very few people are able to put those capabilities to real use with the current crop of system architectures, applications and games available

    --
    I gots ta ding a ding dang my dang a long ling long
  13. Why you want 128MB. by Tokerat · · Score: 5, Insightful

    Quartz Extreme.

    Ok Ok, so it's a Mac OS X thing, so what? How long before M$ innovates this feature into Windows? How long before it's patched into XFree86?

    Think of all the cool things you can do, both for visual pleasure and UI functionality by operating in an accelerated, 3D enviroment, while the main CPU is free to crunch away at whatever it is you have your CPU doing, thus improving overall speed. Yes, I realize the CPU still has to intruct the card of what to do, but at least we're not blitting as we're trying to host web pages, for example.

    For that you're going to need texture memory. Lots of texture memory. When you run out of memory on the card, the framebuffers must be stored in RAM. When those framebuffers are needed, you'll need to swap them into the card's RAM. This will cause the main CPU to stutter as it pumps a couple 8-9MB buffers through the system & PCI bus, which, needless to say, will get old fast, especially if the framebuffers get paged out to a swap file. Yuck!

    Of course, maybe you should wait until the other 2 of the Big Three implement this in some form (I know some work as been done on a 3D window manager for X, no idea if it's meant to take advantage of acceleration, though). I've heard rumor that M$ is working on it for Windows XP(ensive) 2005 or 6 or whatever it is, and I'm sure some Linux hacker has it working on his overclocked Athlon box already. Either way, you probably want to be ready for this. Or wait and buy a card when it finally happens, when 128MB will be standard.

    Since color depths will probably never exceed 48-bit (32-bit + alpha), screen resolutions are fine at 2???X???? or whatever the current highest is, it'd take quite a few windows open at once to framebuffer all that memory up. Assuming about 8 megs per window, which is admittedly above average for most windows (sans Photoshop or web browsers), you'd get about 14 or 15 windows open at once.

    Oh well, someday, you'll be sorry your card doesn't have 512MB on-board :-D

    --
    CAn'T CompreHend SARcaSm?
  14. Tim Sweeney endorses texture caching. by Vegan+Pagan · · Score: 3, Interesting

    Here's what Tim Sweeney says about texture caching:

    "This is something Carmack and I have been pushing 3D card makers to implement for a very long time. Basically it enables us to use far more textures than we currently can. You won't see immediate improvements with current games, because games always avoid using more textures than fit in video memory, otherwise you get into texture swapping and performance becomes totally unacceptable. Virtual texturing makes swapping performance acceptable, because only the blocks texels that are actually rendered are transferred to video memory, on demand.

    Then video memory starts to look like a cache, and you can get away with less of it - typically you only need enough to hold the frame buffer, back buffer, and the blocks of texels that are rendered in the current scene, as opposed to all the textures in memory. So this should let IHV's include less video RAM without losing performance, and therefore faster RAM at less cost.

    This does for rendering what virtual memory did for operating systems: it eliminates the hardcoded limitation on RAM (from the application's point of view.)"