DDR 4 sets the pace for fast memory Reducing the size of chips has benefits beyond those seen in CPUs and GPUs. One other key component to gain an advantage is memory. The specification of the next generation of memory module, DDR 4 (DDR stands for 'double data rate'), is currently being finalised ahead of its anticipated launch later this year. It will use less …
The extra memory bandwidth is surely very important for higher performance APUs, so I expect AMD will be investigating using DDR4 seriously.
However the change in topology surely makes it difficult to create a DDR3/DDR4 compatible memory controller to ease the transition, and the cost of DDR4 will be high upon release compared to DDR3.
For most performance-oriented laptops available now, there are two DIMM slots, each on their own memory channel, so the motherboard already has roughly as many wires running from the processor socket to the DIMM slots as would be needed for DDR4. Getting more bandwidth and better power usage for laptops is a pretty clear win.
This is not such a clear win for higher end desktop or server boards which currently run multiple DIMMs per channel. Remember that one of the selling points for FBDIMM was supposed to be that fewer wires per channel meant it was possible to fit more memory channels onto a motherboard at the same price point. More layers to fit more wires == more expense. Other factors weighed against FBDIMM more than this advantage, so it's unlikely to resurface... but the economics of cramming wires onto boards are largely unchanged.
Samsung are only saying that the maximum speed of the first DDR4 modules will be 3.2Gb/s as opposed to the 4.266Gb/s the specification allows for.
As for the speed you actually get, put them into a board that is only capable of, say, 2.0Gb/s and that is the speed you will get. You may as well complain that the petrol you put into your Ford Ka doesn't go as fast as the petrol you put into your Bugatti Veyron (although I dont know why you would use a Ka when you have a Veyron).
I would have accepted this until the downside was mentioned...all slots needs to be filled. OK, not a problem is you have a server maxed out on memory but if this is not the case then power consumption is going to go up.
Lets say there are eight memory slots in the server and four are used up. 8GB in each slot, 1.5v per DIMM. That's 6v. With DDR4, this will use 9.6v whatever the capacity you choose.
@Tom 38: His statement is incorrectly put but I believe his premise is correct - when voltage isn't additive then current is and vice versa. The system will use more power if you assume both types of board use the same current. 1.5 x I x 4 against 1.2 x I x 8 gives 6 x I versus 9.6 x I (and I wish this was a different font). Hence, to get the benefit of the system you can end up using more power unless you fill the memory to capacity.
One of the consequences of knowing the diference between Volts, Amps and Watts is the painful twinge you feel when they are misused in conversation or reporting. The pain is felt quite often and I suggest it is even worse than the pain others feel from the whole there, their, they're problem.
No, it doesn't mean the 0Mb stick will return. What it does mean is this...
The CPU's memory controller will have X number of pathways running to one of the chips on the DIMM module, kinda like PCI-e lanes, each lane can transfer data from it's chip simultaneously. When you leave a socket unpopulated, the memory controller will have unused pathways sitting idle, lowering the transfer rate, reducing memory bandwidth.
....going to DDR2 then 3 and now 4 has just meant that messing around buying Turbo Nutter Mega Ram sticks with 'super low timings' has become largely a waste of time and money.
Just buy the good standard Crucial/Corsair/Kingston stuff and get on with your life.
If you have to buy fancy then just choose which heat spreaders look best with your motherboard.
It's not likely many will be rushing to DDR4 as it will be pricey and only of value for server use. A typical DDR3 DIMM only uses ~10w so lower power is good, but let's not get carried away with what it means in the big scheme of life.
Desktop PCs have no need for DDR4 as DDR3 is not saturated and still has plenty of available bandwidth to be used. The need to populate ALL DIMM slots is a serious negative for DDR4.
"The need to populate ALL DIMM slots is a serious negative for DDR4."
See, I thought the same thing to start with. I remembered the bad old days when, if upgrading your PC RAM, you had to buy matching pairs which often worked out VERY expensive. If you had a mother board with two pairs of slots and one pair had 2 X 512MB DIMMS to give 1GB of RAM you couldn't just buy another 512MB DIMM. You had to buy two thereby doubling the cost.
But, with the PC becoming more and more of a consumer product I'm not sure that matters any more. Yes, there will still be the enthusiast market for whom it will be an added expense. But then, when speccing a high-end gaming rig or video editing machine you expect expense.
The vast majority of people now buy laptops, tablets or all-in-one PCs which either can't be upgraded or just won't be. And I can't remember the last time we added RAM to a PC at work. It used to be a regular occurance but, with Windows 7 (and 8) having the same memory requirements as Vista, RAM hasn't really been an issue for the last several years.
If there was a need or even some value in DDR4 for desktop use, then maybe people would be willing to pay a premium for it, but there is none. In a laptop where power consumption is a concern, there is still little advantage to DDR4 as DDR3 LV can do the job for a lot less money and with excellent battery life. So servers are the only place where enterprise might sign up for more expensive DDR4 and the only place it is really of any practical value.
Paragraph after paragraph about DDR 4, but not a single word about the maximum memory size of a DDR 4 module! The photo in the article shows only a 2GB DDR 4 (not exactly impressive, since 4GB DDR 3 sticks have been around for ages) and I was hoping that we'd see 8GB DDR 4 modules as common as 4GB DDR 3 (yes, there are 8GB DDR 3 modules, but they're actually moderately rare) and maybe even 16GB DDR 4 modules?
It seems bizarre to me to raise the specs of everything in DDR 4 compared to DDR 3 and yet we're completely in the dark as to the maximum size of DDR 4 modules.
Most people have no need for more than 4-8 GB. of RAM for a desktop. Servers obviously can use all the RAM they can get and since DDR4 is designed primarily for server use I'd expect 8 GB. DIMMs to be the norm and 16 GB. DIMMs to be an expensive upgrade.
Hi, only 2Gb/s is the top end of current memory? Doesn't that mean that 3Gb/s Sata2 and 6Gb/s Sata3 etc is all a pointless (presuming you've got raid 1 SSDs connected to it so you can actually pump that kind of data speed) waist of time since it can't get the data into memory due to memory bottlenecks?
How can 10Gb/s ethernet work if we can't physically get data out of memory that fast? Can someone get me up to speed. Ta
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the reason they are slow to uptake this is clear why have 2Gb/sec with higher power DDR4 when you can have 100Gb/s and up to 2 Tb/s or 250 GB/s bandwidth in the near future with Wide IO2 512 bit 4x128 stacked DDR3 modules that's four parallel, independent, 128-bit memory channels ;)
uk so the first Wide IO isn't as fast initially at only up to 17GBps operating at 200MHz for a massive power saving in comparison but its JEDEC ratified and their also lookin gto ratify version two soon too, all bets are off for DDR4 Wide IO is the plcae to be now and in the near future, the PR people will just have to call it DDR Wide IO or something and pretend its DDR4 ;)
http://eda360insider.wordpress.com/2011/12/14/3d-week-wide-io-sdram-network-on-chip-multicore-tsv-asynchronous-logic-3d-soc-stack-from-cea-leti-and-st-ericsson-hits-all-the-advanced-notes-can-you-say-tour-de-force/
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