DDR4 RAM To Hit Devices Next Year 233
angry tapir writes "Micron has said that DDR4 memory — the successor to DDR3 DRAM — will reach computers next year, and that the company has started shipping samples of the upcoming DDR memory type. DDR4 is more power-efficient and faster than DDR3. New forms of DDR memory first make it into servers and desktops, and then into laptops. Micron said it hopes that DDR4 memory will also reach portable devices like tablets, which currently use forms of low-power DDR3 and DDR2 memory."
Re:Isn't it time to drop the "D"? (Score:4, Informative)
Re:Latency? (Score:5, Informative)
13 clock cycles according to the all-knowing Wikipedia [wikipedia.org], so similar to the latency increas going from DDR2->DDR3; theoretically it will be made up for by increasing clock frequency, I guess, with DDR4 starting at 2133 MT/s (unfortunately I'm not clear on how transfers/s translates to MHz for DDR4 - is it the same two transfers per quad-pumped cycle?).
Re:Latency? (Score:5, Informative)
Latency has significantly decreased, thanks to higher clock frequencies. See the chart on this page: http://en.wikipedia.org/wiki/CAS_latency [wikipedia.org]
But RAM will always be slower than L1 and L2, simply because of the size of the memory.
Re:DrrDrrArr (Score:5, Informative)
QDR's already around. In fact, a popular console already uses it. It's still heavily patented though, so it's not very appealing.
The Playstation 3 has 256MB of XDR-DRAM by RAMBUS (yes, that RAMBUS). It does QDR - two bits on falling edge, two bits on rising edge (using multi-level signalling).
It's tricky for memory because the bus speed is high, signalling ovltages low, and motherboard traces bad enough that the eye window is very small, so a lot of (patented) tricks are needed to "open up" the eye and recover the bits from it. Impedance mismatches are a killer (and they happen at connectors especially).
Re:Would have gotten a FP except (Score:5, Informative)
How does crap like this get modded insightful? Oh wait.. it's because it plays up to the bigoted prejudices that prevail on this site.
1. I've actually used the Windows 8 preview on a 4 year old PC and it is more responsive than Linux for desktop use. I don't like Metro, but everything under the hood in Windows 8 is in very good shape and some changes to the UI could make it a good successor to Windows 7.
People on this website who brag about being Linux "experts" because they got Ubuntu to boot one time should know the difference between the UI presentation layer and the underlying OS services. Unfortunately a bunch of self-proclaimed "experts" who troll this site are anything but.
2. I also use KDE on the desktop and I've used LXDE. Guess what? KDE is faster for my use because of the ability to reconfigure its setup. I don't want or need a taskbar to switch between apps, and because of KDE's flexibility I have a very efficient keyboard shortcut system in place to handle window management. Additinally, yakuake gives KDE a big edge for handling the konsole in a smart way and guake (which cloned yakuake) is still not as good.
Firefox under KDE starts up in the same amount of time as on LXDE.. and so does every other application I try. Windows don't move faster across the screen on LXDE either and they resize at the same speed on both desktops!
Re:DrrDrrArr (Score:5, Informative)
DDR2 effectively *is* QDR –it transfers 4 words per clock cycle... It just doesn't do it in quite the same way that true QDR RAM would. DDR3 effectively is ODR (octa-data-rate) RAM. DDR4 will effectively be HDDR (hexa-deca-data-rate) RAM.
Re:Tell me again how this improves my life... (Score:5, Informative)
The initial DDR4 models will be only marginal increases over DDR3, true. But remember how the original DDR3 models were only marginally better than DDR2, or even how some initial DDR2 modules were *worse* than DDR?
DDR3 is hitting a wall, where increasing the frequency any further is causing exponentially higher power usage and heat. I can't find any air-cooled DDR3-1866 or DDR3-2133 - every module I can find is water-cooled, because that's the only way to dissipate the heat. DDR4 begins at DDR4-2133, apparently without even needing a heat sink. And it's expected to scale to double those speeds, over time. And *those* you *can* upgrade - if you buy a DDR4-2133 device now, you can upgrade to DDR4-3200 or DDR4-4266 whenever you wish, if your memory controller supports it.
DDR4 is also making a rather significant shift in architecture, going from a dual/triple/quad-channel-memory paradigm to a point-to-point system. So better scalability with multiple modules.
Oh, and one quote cited a 40% decrease in power usage compared to an equivalent DDR3 module. That's hardly "slightly" lower.
Re:Would have gotten a FP except (Score:4, Informative)
You say that like a bad thing? Low-end machines today have 8GB. My desktop at work has 32GB. I want Windows to "waste" as much memory in an effort to minimize physical I/O as it possibly can! Needing to go to even the lowest-latency-on-the-market SSDs means potentially "wasting" 250 thousand CPU cycles. An HDD, more like 25 million. And if you actually need to wait for an idle HDD to spin up or a network request... Ouch!
In any case, keep in mind that flushing the FS cache doesn't mean hitting the pagefile. You may need to actually hit the disk if you then go to access something that got dumped, but you would have needed to anyway if Windows hadn't cached it in the first place.