DDR4 memory is finally making its way to the mass market, three years after it was initially sampled and nine years after work began on it. Given where it will most likely be used, there's a reason they went so slow.
DDR4 will take off in servers first, a change from past memory introductions. With DDR, DDR2 and DDR3, they were introduced on desktops, then moved to laptops and servers. Here it's reversed, because DDR4 will most benefit servers. As a result, the server and memory vendors were much slower and more deliberate, taking far longer than usual to qualify the memory because servers cannot tolerate down time.
DDR4 has a number of improvements over the current generation of memory, but it comes down to two big changes: lower power requirements and faster bus speeds. The power draw drops by 20%, from 1.5 volts to 1.2 volts. In a server with hundreds of gigabytes of memory, up to 1TB, that will really add up as you add more memory sticks.
An even bigger savings comes from the fact that DDR4 will have much higher chip densities. SK Hynix of Korea has already announced a 128GB DDR4 memory module. Anything past 8GB in capacity for DDR3 was prohibitively expensive.
Not that DDR4 will be cheap. IHS (formerly iSuppli) estimates DDR4 will be 40 to 50% more expensive than an equal capacity DDR3 module and the two won't become equal in price until 2016. But if you have the money to deploy a server with a terabyte of memory, this probably isn't too much of a problem.
The other big change is speed. DDR3 topped out at 2.1Ghz. DDR4 is being introduced at 2.1Ghz and some modules at Computex are above 3Ghz. In theory, DDR4 could hit 4.2Ghz.
Some people have told me that above 1.8Ghz, memory performance really levels off, but that's on desktops. In a server environment, where there may be hundreds of virtual machines running at the same time and gigabytes of data I/O into and out of the server, that could make a difference. Time will tell.
DDR4 won't go mainstream until at least next year. Intel announced its first DDR4 chipset, the X99, which will go with its Extreme Edition CPU. The Extreme Edition is for crazy overclockers and gamers who want every last volt of speed they can get. The Extreme Edition CPU alone is $999, plus the rest of the parts. IHS said they sell maybe 100,000 units per quarter, but it's a highly lucrative market.
So, among the new products at Computex:
* ADATA showed solutions that start at 2133MHz and will go all the way to up to 3200MHz. Besides the price difference, there will also be differences in memory latencies between the 2133Mhz chips and 3200Mhz chips. ADATA will offer DDR4 in 8GB and 16GB kits, with two memory sticks per kit.
* Corsair showed off Dominator Platinum Kits for enthusiasts, running at 2400MHz speeds, while the Value kit was at 2133MHz, the minimum speed for DDR4 memory.
* Crucial announced the Ballistix Elite brand of DDR4, with speeds of 2666MHz and 3000MHz and modules of 4GB or 8GB at first, which could eventually reach 32GB.
* G.Skill showed off 4GB modules and 8GB modules with varying speeds, from 2133Mhz to 2666Mhz.
Server vendors will be snapping up these modules this year, and by this time next year, we should see a mainstreaming of DDR4 in desktops and laptops. In the mean time, I'm in no hurry. These days, the slowest component of my PC is me.