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GDDR2 Emerging As A Real Standard

Posted by timothy on from the sharpen-the-initiative's-spearhead- dept.

An anonymous reader writes "I noticed here that EE Times is reporting that the GDDR2 standard is finally becoming a reality. Both NVIDIA and ATI's latest chips offer support. ATI helped spearhead the initiative to develop the standard. The significance of this is great, since it may very well mean that every 18 months or so a new graphics memory standard will be released."

7 of 122 comments (clear)

  1. last I remembered by lingqi · · Score: 4, Informative

    the special requirement of graphics specific RAM is the simultaneous in/out access. (At least that's my understanding of VRAM (video RAM))

    For that point, why arn't they doing a QDR architecture? QDR is basically DDR but with dedicated in / out pins (separate) that allows this kind of simultaneous read/write.

    Granted, pin count is higher but I think it would be better suited to the graphics people.

    That or I am not quite clear on the GDDR-n specs. heh. Or I am thinking about frame-buffer memory instead of texture memory (AFAIK the latter only need to be continuously read, really fast) hmm...

    --

    My life in the land of the rising sun.

    1. Re:last I remembered by videodriverguy · · Score: 4, Informative

      VRAM was a dual port RAM, with an output only port and a standard I/O port. The output port was used to refresh the screen, since it could produce data independantly from the I/O port.

      However, with the bus widths being used by GPUs today (128,256), they really don't fit anymore. GPUs now manage the RAM accesses so that frame buffer access is shared with drawing etc. This means that the most important thing is RAM speed - with accesses for the frame buffer being sequential, the less time taken for that the more memory bandwidth left for drawing.

      This will become even more important once we have the very high resolution monitors (LCD) on the horizon - 3K x 2K pixel displays will require a LOT of memory bandwidth to keep them refreshed.

  2. Re:I'm sorry... by Doppler00 · · Score: 4, Informative

    Probably because it's engineers and not marketing people naming these things because it's being sold to other firms to be included in there products. I guess Engineers prefer unintelligable acronyms to cool names like GeForce or Radeon.

    GDDR2 SDRAM really means -> Graphics Double Data Rate 2 Synchronous Dynamic Random Access Memory

  3. Re:Maybe... by Anonymous Coward · · Score: 1, Informative

    "GDDR3 will consume half the power of GDDR2 and operate up to 50 percent faster."

    Uhm read the article:

    "Lee said Micron's GDDR3 chips are made with 0.11- micron processing, allowing speeds that could reach 700 MHz for a 1.5Gbit/s data rate. The device will sample next quarter, he said"

    GDDR2 reaches 500MHz now, GDDR3 _could_ reach 700MHz sometime in the future. By that time GDDR2 will reach at least same speeds. AFAIK frequency goal for GDDR3 is 500MHz in Q3.

    "Look at the GeForce FX. It's going to kill NVIDIA."

    Don't forget that GeForce FX describes a whole family of GPUs instead of just high-end part (NV30) which will be replaced by NV35 in the May.
    Since $79 GeForce FXs will be available quite soon, GeForce FX will be very popular.

  4. GDDR3! by nrdlnd · · Score: 3, Informative

    The good news in the article is that the much "better" memory GDDR3 will be standardized from the beginning with may suppliers and hopefully a lower price. Forget GDDR2!

  5. Re:GDDR2? by EinarH · · Score: 4, Informative

    It's hard to find any technical description since its pretty new and there is no JDEC-standard yet.

    But the key that makes it worth the extra bucks is the fact that DDR-II delivers twice the external bandwidth of a standard DDR solution for the same internal frequency. The 1.8-volt device features a high-speed data transfer rate of 533Mbps that can be extended to 667Mbps for networks and special system environments.

    The last year chip-makers have released diffrent DDR chips with increasing frequency like DDR 266, DDR333 and DDR400. But its limited how much higher its possible to go so instead they are trying to add another sort of "bus" inside the chip.

    The reason they started producing DDR (vs. SDR) is because it's much easier to implement such a double data rate (DDR) bus than it is to actually double the clock rate of a bus. So DDR allows you to instantly double a bus's peak bandwidth without all the hassle and expense of a higher frequency bus.

    DDR-II is made thinking in the same way.

    --

    Melius mori in libertate quam vivere in servitute.

  6. VRAM wasn't just dual port RAM by Anonymous Coward · · Score: 1, Informative

    One of the port was a normal R/W port, and the other was a read-only port. This port also had a very wide word-size. That is, you would select an entire column of the RAM (2K bits back then, 4K or 8K now) and it would parallel load it into a internal buffer, then shift it out bit by bit. This may sound very slow, but it was VERY fast, and you only had to deal with latency with each parallel load, so every 2K to 4K bits. This system was ideal for video display and still is.

    Also note that latency is a relatively minor issue when refreshing video since you read the memory in an absolutely predictable, sequential way, so you know far enough ahead of time to ask for the data in order to have it ready when you need it. Bandwidth is a larger issue, back when 1024x768 (at 32 bit) was big time, video cards had 4 or 5 banks of memory in order to keep up. It would be worse now.