DDR4 memory?

[Konrad]

I don't see USB, PCI-e, SATA, etc disappearing any time soon; they're standards designed for compatibility with off-motherboard hardware, they're reasonably well designed and they allow all the hardware makers who aren't working in mobo factories to contribute to PC technology.

But these days the chipset (most especially the Northbridge/MCH component) is basically half of the computer, soldered onto the mobo, designed in tandem with whatever family of processors plug into the mobo socket. The "standards" for these parts (along with the parts themselves) are made by Intel or AMD; how the CPU and mobo communicate isn't relevant as long as it works and all the other hardware (PCI-e, USB, RAM, etc) that plug onto the mobo still follow normal industry standards.

The consumer would basically just see a mobo with all the usual hardware connectors (and the usual "new" proprietary processor socket) plus perhaps a few more slots to populate with RAM sticks. Graphics cards with their own onboard processors and memory and memory controllers have already done this for years; the simple truth is that they can operate faster when computing and manipulating data locally instead of sharing memory with slowpoke main processor priorities ... these cards even bridge directly through each other rather than share data through the mobo chipset. Imagine a PC where each processor core has its own memory, where they can bridge data directly to each as well, independant of whatever wait might be queued at the (one or two or even three) memory controller channels used today.

It seems like a sensible evolution to me, since RAM ain't all that costly these days and we've already seen the focus of PCs move away from "one big fast brain" to a distributed multi-core (and increasingly parallel) architecture.

[RogueOpportunist]

DDR4? With these new APU's using system ram I can see AMD pushing for DDR5 before 2012 is out... They need the edge on Intel wherever they can get it and they aren't going to keep that edge by using DDR3 for graphics memory, even if it is a "mid-range" offering.

Think about it, you could theoretically take a GT460, put DDR1 memory on it and make it worthless as a "modern" video card... Seems like a stupid statement... Until you realize that this is almost exactly what AMD has done by forcing the GPU to pull from system memory... I mean it works O.k. for the time being but reading through some of the more thorough reviews it's pretty plain to see that people have already noticed the "compromises" AMD had to make that have resulted in bottlenecked performance.

AMD has no choice but to push for DDR4+ as system ram, they NEED it like they need silicon, without it 2012 completely falls a part for them... The only real savings grace in all this is that as far as "graphics" goes AMD could release a steaming dog turd and it would still outperform any Intel IGP offering.

[Konrad]

Why is this "need" for DDR4 limited to AMD? Intel and nVidia have the same pressing interest in faster memory, and they'll certainly offer their own APU architectures (although perhaps under different names) if the approach actually proves effective.

The APU approach gives higher integrated performance at the cost of lesser modularity; an AMD APU computer might have top-tier components at the outset but it won't compete with even better processing components being offered 1-2 years later. In a way, it's more all-or-nothing ... gotta upgrade the entire platform all at once rather than just individually upgrade the weakest components; this might not be an issue if a multicore APU is priced comparatively to discrete multicore CPU and GPU components. Probably a terrible thermal nightmare as well, concentrating all those busy electrons in such densely integrated parts - although price, performance, and reliability factors still remain to be seen. I suspect this approach will see a lot of use in laptops and other mobile platforms, which is great, but nobody breaks records or builds über-gaming boxes from laptop components.

[RogueOpportunist]

Easy answer to that, Intel does not "need" faster DDR since they do not have high end graphics integrated into the CPU that demands it... As far as Nvidia goes... Well... They don't need what they already have.

By putting discrete level graphics on-die AMD has locked themselves into a future demand for faster desktop memory, not because desktops "need" faster memory, I mean lets face it, even the difference between 800mhz and 1600mhz RAM is barely noticeable to 80% of computer users but enthusiasts want faster DDR because it makes their wang longer, it's pretty much on par with Extreme Edition processors, 600$ motherboards and triple channel memory.

Introducing faster DDR is like coming out with 64-bit processors, it's not "new" tech, it has been around for quite some time now, the only reason we haven't seen faster ram already is because there is no demand for it... I know the first response to that is going to be "then why do we have 1333, 1600, 1800mhz, etc.. Well...That's easy... They're not making higher level ram chips, all those chips are made at the same time, it is the exact same product, what you are paying for is a higher bin... The same as with CPU's... They aren't making faster product... They are just labeling it as faster product.

Watch, in 2012 you're going to see the exact same conversations people had about the "validity" of triple channel memory, except it will be in the context of DDR4. I can see AMD platforms going up in cost due to their graphics chips demanding faster memory, while if Intel is smart they will just flip it around and offer cheaper triple channel DDR3 alternatives and take what was AMD's argument against triple channel and flip it around on DDR4... That won't happen though, Intel will push anything they can on the market.


This is of course just my opinion and I have absolutely no clue what the future holds... All I see is what's presented and right now AMD "needs" faster memory while Intel doesn't.

[Konrad]

As you say, DDR4 is just an evolutionary increment. The higher bin is the result of finer engineering tolerances; smaller scale and tighter integration ... so yes, there is higher yield of parts which can sustain faster performance specifications.

The RAM modules themselves incorporate a controller chip; this is where the voltages and SPD timings and other parameters are firmwired into place. This onboard controller is not especially complex but it needs to be the fastest component on the module, otherwise it slows down data throughput for the faster RAM chips.

I don't really see any great demand for APU architecture at this point, since we don't have a lot of high end graphics cards saturating all the bandwidth on the mobo's PCI-e 3.0 bus (under normal circumstances), especially since GPU cards bridge directly into each other. I sort of expect the first APU offerings won't be spectacular in real use, although they'll give AMD a head start on the race.

AMD could just as easily accomplish faster memory bandwidth by stacking more RAM slots and channels ... memory is cheap enough that soon it might be cheaper to implement it this way, DDR4 is still too new to be good bang for the buck. The biggest limiter is actually mobo real estate; everybody likes to miniaturize the form factor as much as possible and RAM slots take a lot of space. I imagine AMD's Northbridge chips will run a bit cooler because much of their heat will be transferred into the APU core (since many more signals will be isolated on-die instead of directed across mobo data busses). I hope they don't decide to cheap out by removing PCI-e lanes from this component of the chipset, I hate it when mobo makers splice extra lanes into their boards because it always invokes some kind of tradeoff.

Yeah, of course we'll see "hybrid" boards which can accept new DDR4 and current DDR3 (and perhaps slower DDR types as well), at least for a while, as usual. Every new generation (new socket) processor looks great at introduction but quickly ends up becoming the bottom offering within its family, and first-gen mobos usually end up having all sorts of minor flaws which get corrected in future revisions (not always possible to fix with BIOS firmware updates). I personally think it's worth waiting until the first wave has passed, oversights get properly fixed, and prices shuffle a few steps down the ladder.

[RogueOpportunist]

I'm not trying to open a debate on the methods of use or the willingness for manufacturers to push product to market long before there is a demand and relying on marketing tactics to make sales figures... All I'm saying is AMD "needs" that ram to be faster, when I say that I am considering that their APU offerings aren't going to remain static, while I doubt APU offering will be as aggressively "revamped" as GPU offerings I do see the very next offering as being something that will make todays product look pale in comparison... I mean it just makes sense right? The 100$ GPU of today was the 400$ GPU of last year... or hell 6 months ago.

AMD's current APU offerings have a memory bandwidth bottleneck, it is their very first APU and already the memory is an issue. Given the current trend with GPU development I wouldn't consider it far fetched to say that the next APU offering isn't even going to function on DDR3 due to that bottleneck, it is a compounding problem, what might only translate into a 10 or 20% drop in performance today could translate into a 50-75% drop in performance on the next gen GPU's... It's like with my GT460 example... Put DDR1 on any modern video card and you render the thing useless by modern standards, you couldn't sell the thing for 5$ if you wanted to, the memory bottlebneck is just too severe and the GPU can't function properly... Well my opinion is that the exact same thing is going to happen with DDR3, eventually the evolution will come to a point where DDR3 is just no longer functional as video memory, at which point Intel won't care because they don't have a "high end" IGP that needs fast memory and Nvidia won't care because video cards use their own RAM... AMD on the other hand is going to have to do something about memory, what that something is I have no idea but my point is AMD "needs" it... Intel shouldn't really care less one way or the other.

[DemonDragonJ]

you are correct to a certain extent.

the processor already runs parallel communications natively. that's where you get 16 bit, 32 bit, 64 bit, etc. in a 64 bit processor you have 64 bits of data going to the processor at one time in parallel. same thing with an ide port for a hard drive. the data is flowing in x amount of bits per clock cycle. with sata coms it just changes the parallel data into a single stream of serial bits.


but with parallel computing, you would have each core or processor doing it's own thing at the same time as another core or processor. whether their communications are in parallel or serial.

i think that's pretty much how they work now. however, that parallel processing has to go through a single memory controller chip. so that parallel data to and from the processor has to go through the controller chip "serially".

so what konrad is saying is if you give each core it's own memory controller, then that parallel data can go through IT'S OWN MEMORY CONTROLLER "PARALLELY" (i just made a new word).

does that make any more sense?

Yes, that explanation is very helpful, but I now wish to ask: why is parallel computing an apparently recent phenomenon, if multi-core processors have been in existence for several years now? Is parallel computing simply a complex and difficult process to achieve?

[xr4man]

i don't think it is a recent phenomena. i just think the cost has come down enough for it to become main stream for consumer pcs.

although i did read an article a while back about the real world need of 6 core processors and that until there is software that is optimized to use all six cores, it wouldn't be much of a jump in performance. it went on to say that writing code for multi-core processors was a bit more difficult.

i think i read that about a year or so ago, so obviously things have changed, but it's just an example.

[Kayin]

AMD could simply address that memory issue through a sideport. There's also been talk of integrating DRAM into the package like their Xbox360 GPU. They have experience with both.

Besides, there's talk they'll abandon DDR altogether. Their newest cards (HD7000) are all running XDR (the newest incarnation of RAMBUS) with a quad data rate, not a dual. It's not too big a leap to put the desktop version into their setups. Yes, it's a respun processor, but DDR4 would be as well-the IMC will not handle it natively.

DDR4 isn't JEDEC certified, so it will be 2014 at the earliest before it comes out. I expect AMD to go with sideband addressing soon, and for Trinity possibly an integrated DRAM cache plus sidebanding to deal with the HD7000 series core in it.

Sturm und drang, but no real DDR4 till 2014. Could AMD benefit? Dubious at best. First gen DDR4 will most likely (like DDR2 and 3) be slower than DDR3. Only over time will it ramp up.

[Konrad]

The embedded microcode running in the processor hardware actually automates efficiency to some degree, but yeah, the software needs to be optimized to gain full use of the hardware. Modern compilers and operating systems automate this to some extent as well, but the reality is that even the best automation is dumber than smart design. Most programs do not lend themselves well to parallel computing anyhow; the result is cores either remain idle or are tasked with running other programs.

Software will never fully utilize the latest and greatest hardware technology anyhow, it's always slightly behind the curve, but it'll never catch up if the hardware is not introduced.

In any event, while faster is always better, I still don't see high-end DDR3 being obsolete for a few years; the components which require critical memory speed (ie: CPU and GPU, mostly) already integrate their own dedicated memory controllers, it's not at all difficult to double your word length by addressing twice as many RAM chips through a glue logic controller, doubling and redoubling your memory bandwidth right up to the architecture limits imposed within the processors themselves ... it just costs more.