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An Overview of Quad Band Memory
tedgyz writes "AnandTech has a short article on a new memory technology from Via, called Quad Band Memory (QBM). Rather than using dual-channel DDR to increase bandwidth, they use phase-shifting inside the memory modules to accomplish the same goal. The end result is simpler (and presumably cheaper) motherboard designs that are backwards compatible with current DDR modules. The downside? It is currently only going to available in a P4 chipset that Intel has not authorized."
hmm, i wonder what the commercial applications of this are :)
The downside? It is currently only going to available in a P4 chipset that Intel has not authorized."
Keyword: currently. I'm sure the technology will be available soon for plenty of other motherboards. I don't consider this much of a downside (feel free to set me straight if I'm wrong).
Slashdot: Where people pretend to be twice as smart as they really are by behaving like children.
..."technical" articles by high school drop-outs.
"Hey, I can install Windows! Read my super 1337 happy fun article on the latest and greatest gfx card!"
What do you want to bet that you'll be able to find more than your fair share "QBM compliant" montherboards that do NOT play happily with a large chunk of the available "QBM" memory and visa versa?
Please keep all this pseudo hardware news bullshit off the site and leave it to people who KNOW WHAT THE (*&^#%#@$ THEY ARE TALKING ABOUT.
Given the memory manufacturers' resistance to DDR400 and the achingly slow progress that DDR2 is taking (the module standard isn't even final yet), this technology has a pretty good potential to reach production.
-h-
...how long will it take for the major chipset makers (Via, SiS) to adopt this technology? It'd be great to see this available on the Athlon platform in the near future.
If you can't beat them, arrange to have them beaten. -George Carlin
From the article:
*snip*
Here's where the difference between QBM and conventional modules comes into play; QBM modules will have a set of 8 registers (QBM-10) as well as a phase-locked loop (PLL). The purpose of the PLL is to take the incoming clock signal from the chipset and shift it by 90 degrees; this shifted signal is then fed to the second bank of the DIMM, while the first bank receives the unaltered clock directly from the chipset.
The 8 registers then switch between which bank gets to transfer data every clock; because of the 90 degree phase shift, there is a slight delay in transferring data from the second bank but both transfers actually end up happening within a single clock cycle. The end result is that you get two DDR transfers per clock, or 4 bits of data are sampled per clock thus doubling the throughput of DDR (hence the name Quad Band Memory).
*snip*
QBM modules will obviously be more expensive than regular DDR modules, the question of how much remains to be answered however.
Let's see, one PLL... damn, I don't know if I can afford the extra six cents!
(That extra six cents though doesn't detract from fact that this idea is just pure genius... with about 30,000 folks slapping their forheads for not thinking of it first!)
but the cpu is still stuck at 533mhz with the athlon (should this be available for it anytime) is barely going to a 333mhz fsb
Via made this, via makes chipsets. Seems likely they'll make chipsets that support this.
If it's *that* simple to double the data rate of memory, why don't they, for example, divide the memory architecture into eight sectors and have each bit of a byte on a different sector, making 16x memory? It seems that this philosophy has no limit, as long as you have lots of sectors. What's preventing people from doing that?
:).
Sorta like a beowulf cluster of chips, really
In essence, they're putting additional capacity in quadrature. How clever! Memory that shares technology with NTSC color television....
Sry i can't post from my login name, it seems that my bad karma prevents me from posting for another half hour :/
x .html So I ask, will the technology ever see the light of day or will it go the way of the dodo and dataplay.
I've seen several attempts to make faster memory,
one of them I read about about two years ago and can be found here: http://sysopt.earthweb.com/articles/qdr-sram/inde
I'm sure a few applications will make this into the mainstream, but what makes this any different from any other high speed memory attempt?
the chipset will begin sampling in Q1-2003 and it will ship by the end of Q1-2003
With the lastest news about Intel including DRM into the next major processor release, it would be smart for AMD to grab hold of the QBM memory and to use it for their advantage. If AMD will grab hold of this memory and run (since Intel wants to drag its feet), it will have 4.2 gigs/sec bandwidth for memory. With the news about the Opteron coming out in Q1 of next year, this would be optimal for AMD.
The combination of the AMD Opteron x86-64 with QMB553 (4.2GB/s bandwidth) would make the issue of waiting on memory less noticable. It would be in the best intrest of AMD to take the QMB memory and run while Intel still drags its feet.
Is that teaching computers how to engineer other computers?
they use phase-shifting inside the memory modules to accomplish the same goal.
Isn't phase-shifting what happened to Jordi and Ensign Ro causing the crew of the Enterprise to think that they had died in a transporter accident?
Or is phase-shifting what the Traveler used to send the Enterprise to the center of the galaxy?
In any case, I don't ever recall Star Trek using phase-shifting to increase memory bandwith. Something's amiss here.
Because of the pin-compatible DDR interface, QBM chipsets will be able to use both regular DDR SDRAM modules as well as QBM modules.
That's a GREAT feature. If i have 1GB of DDR ram and only enough money to upgrade the mobo, i'd go with QBM because of this. Then later on the switch could be more gradual. Backwards compatability is a good thing, just look at the PS2 and how well it sells.
DDR333=2.7GB/sec bandwidth
QBM667=5.3GB/sec bandwidth
Double the bandwidth with small modifications to a regular DDR chip has potential for growth.
It seems that the only problem now is that it won't be out until the end of Q1 2003, and it will be on P4s... hopefully they won't have Pallidium too.
-=Errors always defy logic.=-
It probably will cost a buttload of money
There are only 10 kinds of people in this world... those who understand binary and those who don't
Nowadays, you see all of these benchmarks on chips/chipsets/memory, and unless you're talking inSANE resolutions and color depths, AMD/Intel vs nVidia/ATI really doesn't matter much. It's just personal preference.
:)
Memory as well - how many of you TRULY saw a difference between PC100 and PC133 DRAM? Yeah, the benchmark numbers don't lie - but again, those are JUST benchmarks. Regardless, I don't think the system is being held back by memory.
It was my understanding that the major bottleneck of any system is the DISK. So no matter how fast your ram is, if you still have to swap to the slow-ass disk, your system will be slow.
However, I only have a 1Gig Duron w/512M PC133, so I don't exactly follow the bleeding edge. Your mileage, of course, may vary.
GIR: I'm going to sing the Doom song now. Doom doom doom doom doom doom de-doom doom doom doom doom doom doom...
This is a link to kentron's FAQ about Quad Band Memory.
Sorry about this, but I have no idea where I am and was wondering if slashdot has forums or something? It's just I was looking for an up to date list of highest selling games of all time, and thought you guys would be the best people to ask... so if there's some forums around here or maybe you can just answer me here? :)
The downside? It is currently only going to available in a P4 chipset that Intel has not authorized.
Come on people! can't you plainly see the chips are on the table here!
This link clearly shows how Intel has known all along!
Open your eyes!!!!
NTSC=Never The Same Colour PAL Rules!
Isn't this a technology that could be combined with dual bank motherboards? This would then provide 4x the bandwidth of standard single channel DDR.
I'm not thinking so much for main memory, but for graphics. Dual Channel DDR2 + QBM would be a very very good thing. Especially on something like Nv30.
Anyone know if it'd be possible to combine the technologies?
Even if Intel doesn't embrace it, AMD should. Fast memory is irrelevant for Athlon, but Opterons (especially multi-processor Opterons) could seriously take advantage of this.
Make a reference board, and others will follow suit.
/^[A-Z0-9._%+-]+@[A-Z0-9.-]+\.[A-Z]{2,4}$/i
The downside? It is currently only going to available in a P4 chipset that Intel has not authorized."
Why is this a downside? Why should I give a rat's ass what Intel "authorizes".
Intel sure as hell didn't authorize my Athlon on it's Abit mobo with a Via chipset.
Is there an actual downside to not getting Intel's blessing (downside for consumers, not the company making the mobo)?
What's next, CPUs that use dilithium crystals?
!#@%*)anks for hanging up the phone, dear.
it's amd board compatible then I'll consider this news.
http://www.theddrzone.com/news.asp?id=731
Via has not explicitly licensed the P4 bus. Via insists it has rights to the necessary patents through the purchase of Cyrix. If Intel officially approves this arrangement then they may lose some licensing sales in the future by setting a precedent.
The whole thing is kind of silly unless Intel is making money hand over foot in the chipset market. I wonder if their motivation to discourage 3rd party chipset development is to lock down control over various platform technologies? Sis currently makes P4 chipsets but they have a poor reputation for compatibility. Via has improved their rep by dominating the Athlon market. They might have the necessary market share to take the P4 platform in directions that Intel doesn't want to go.
How could you forget inverting the polarity? That seems to be the cure-all of the 25th century.
I guess it wouldn't do to see Jordi running around with a roll of duct tape and giving malfunctioning gadgets a thump to get them working again.
If Intel doesn't bless a chipset from Via and a large MB manufacturer like Asus declines to make a MB based on this chipset to avoid retaliation from Intel then I would say there is a downside for the consumer.
For example, the expected soft-fail rate of a computer memory system in Denver, Colorado is about 4 times greater than the rate expected at a city it sea level (such as New York City). Even in Leadville, Colorado (which is located at 10,151 feet) the expected failure rate is only about 13 times greater than in NYC. No location in Colorado even approaches 100x.
For more information, see the following paper:It can be found online here.
It is pretty pointless to read those sites every day. You might as well sit out on your lawn and watch grass grow. But if you are about to buy or build a new PC then they are quite handy.
Maybe you prefer to just throw your money at Dell and hope for the best, or you prefer the unbiased reviews of CNET (where expensive is always better). I like having more information at my disposal than that.
I like reading a few reviews from around the net. They each have different sponsors and biases, so you can balance them against each other to get a better idea of the truth.
How could you forget inverting the polarity?
Unlike the first generation SDRAM, which sent a word whenever the clock signal went from low to high, DDR (standing for double data rate, or Dance Dance Revolution, or East Germany) sends a word whenever "phi" (the clock signal) goes low to high or high to low, that is, whenever it inverts. QBM adds a 90 degree phase shift, which lets it send a word 1/4 of a clock after phi rises or falls.
Will I retire or break 10K?
They basically load the level/area into memory and you play, for hours sometimes in the same area, very little disk access until you load the next area or if you have too little memory.
What about continuous-world games such as Half-Life? The whole game is one area. Not all of us have 1 GB of RAM to keep a whole 700 MB CD-ROM disc cached, plus whatever the game needs. On every system I've tried it on, Half-Life freezes momentarily when "seamlessly" teleporting from one map to the next.
Will I retire or break 10K?
Thanks, this is what /. should be about. An interesting technical thread without any bickering. You rock!
Why not place the PLLs on every other bank of normal DDR slots on a motherboard. Banks 0 and 2 would be normal. Banks 1 and 3 would be 90-degrees off. If you want double bandwidth, install DIMMs in pairs like on normal interleaving motherboards. Trace complexity would remain unchanged, motherboards would only need a few PLLs inlined, and we could all get twice the bandwidth using $40 DDR DIMMs...and not have to wait for new memory modules to drop in price.
Just a thought.
Why should I give a rat's ass what Intel "authorizes".
Because you can't get warranty service from a company that's been sued out of existence for patent infringement.
Will I retire or break 10K?
Modern RAM ramps up at such a high voltage that it causes side effects that could be interpreted as signal when combined with other RAMs in phase.
Basically, rather than multiplexing, RAM has just gotten faster.
And as far as being analog devices, and not digital, that's not a very good accessment. While the signal that they produce is analog, they look more like sinc functions in the analog domain than sinusoids. Those kind of functions are good for DIGITAL systems. They are defined in such a way that part of the wave form is considered unusable, and that nothing should interfere with that part of the signal.
Compare that to modem signals, which look a good deal more like sinusoids - nice, slow, smooth curves, by comparison.
I suppose they could be made to phase shift, and do all that sort of thing, but computers as we know it would have to be redesigned to interpret signals much, much differently. We'd have to have wavelet processors, or something like that, and everything would have to go slower.
A good question is whether or not such slowdown would be worth it. Considering how well analog computers have done, perhaps not.
Mod me down and I will become more powerful than you can possibly imagine!
``only going to available in a P4 chipset that Intel has not authorized.''
Ladies and gentleman, here's one fine instance of shooting oneself in the foot. It just proves how stupid Intel is, that they don't want faster memory. I mean, it goes without saying that they aren't _going_ to authorize it...
Please correct me if I got my facts wrong.
I'm not a robot like you. I don't like having disks crammed into me... unless they're Oreos, and then only in the mouth. -- Fry
this quote is at the bottom of slashdot at least once every two weeks. what is going on here?
First off, this is NOT QDR memory. The only benefit to this memory module is that the address and control lines can run at half the speed of the data lines, but you still MUST run the data lines at full speed. So, it is still only 2x the data bus speed. This doesnt solve the problems with tracing high-speed buses. Its very interesting intermediate tech, but nothing special. Dont expect video card MFT's to use this tech, because they are already pushing the limits of a parallel bus running at high speeds with the current PCB tech. QDR is a better tech, and will be MUCH more interesting. Dual bank is cool, but pricey due to more PCB layers.
Playstation 3. Nuff said
Quad bandwidth pr0n!
Interleaved memory dates back to the 286 Cpu's and earlier. This sounds like they have just re-implemented it yet again with the newer speeds and are marketing it as something totaly new.
Definiation from a site on the net:
Interleaved memory, which divides memory into two or four portions that process data alternately; that is, the CPU sends information to one section while another goes through a refresh cycle; a typical installation will have odd addresses on one side and even on the other (you can have word or block interleave). If memory accesses are sequential, the precharge of one will overlap the access time of the other.
I am always doing that which I can not do, in order that I may learn how to do it. - Pablo Picasso
Since when does Intel have to "Authorize" a new chip?????
What if this could also be applied to DDR II (QDR) memory? THAT would give some REALLY impressive bandwidth.
The crappy side is that even if it can be applied, it's virtually guaranteed that the memory industry will take the wimp's way - first introduce DDR II, then wait a few years to introduce the dual-band DDR II. No sense in skipping a generation, that would just mean less revenue, right?
steve
Oh, you're not stuck, you're just unable to let go of the onion rings.
http://www.theddrzone.com/news.asp?id=731
fix the bus speed. BUS SPEED dammit!.
When I first glanced at the title of this story, I thought of memories being shifted four times.
The first look at this Slashdot item prompted the mental image of thoughts regarding past events taking on four interpretations.
When I first read the text above, I imagined remembering something, then remembering it again, and again, and one more time, each time different.
The interpretation which before all others was formed in my mind after I read the information about which this post comments regarded bits of stored information being repetitively read and interpreted in different arrangements, more than three times, but less than five.
Why, no, my name isn't Mojo Jojo, why do you ask?
Good judgment comes from experience.
Experience comes from bad judgment.
I am an ASIC designer, and used PLLs in more than one of our products. It adds 0.5mm*0.5mm of silicon (even less for latest processes), plus some cost for testing it (small compared to the massive cost of DRAM test).
I would expect cost increase on the motherboard side, because multiphase signals are very sensitive to timing and signal degradation. If they need better quality materials and precision board manufacturing process, the MB cost will definitely increase.
These days, silicon is cheap, wires are expensive.