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DDR4 RAM To Hit Devices Next Year
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."
... I'm still stuck on good ole DDR2
Realistically, while there are benefits for "faster", it's no substitute for reducing inefficient bloatware.
Let's call it what it is, Anti-Social Media.
I predict a 33% performance increase going from DDR3 to DDR4 based on my own super-secret analysis of the press release.
What is the expected latency of this new RAM? I've noticed that as the RAM technology has progressed, it has favored pure throughput to latency, but this is not always ideal. Is DDR4 going to help with this, or is this yet another advance that comes at the expense of added lag? Just curious on this. I didn't think RAM bandwidth was a problem, but latency could starve these current ultra-fast processors.
today is spelling optional day.
Double the memory bus clock frequency. DDR runs two transfers per clock cycle.
I just bought a new computer with DDR3 in it yesterday.
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).
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.
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.