User Manual

4
DDR4 WHITE PAPER
DDR4 in Detail
As previously mentioned, the primary benefits of DDR4 are increased bandwidth, a
reduction in power consumption, increased density, and improved reliability.
Increased Bandwidth
While DDR3 kits are available all the way up to 3000MHz, JEDEC only specifies operating
speeds up to 2133MHz. Scaling beyond that requires exceptionally high performance
ICs, making higher speeds harder and harder to obtain. In memory bandwidth bound
applications (such as Adobe Media Encoder and Handbrake), 4th Generation Intel Core
i5 and i7 processors demonstrate performance scaling all the way up to 2400MHz. This is
arguably a limitation of the DDR3 spec, which was never intended to scale this high.
Figure 4: Intel Core i7-4770K, dual-channel DDR3 bandwidth measured in AIDA64.
DDR4 is being introduced to the mainstream at 2133MHz and 2400MHz, but the
specification allows scaling well beyond that. Launch speeds are as high as 3000MHz, and
keep in mind that this is only in the first year. While DDR4 inherits DDR3’s timing methods
and will feature another bump in timing latencies similar to the one DDR3 received from
DDR2, substantial internal architectural changes and tighter yield specifications allow
it to achieve an overall increase in potential bandwidth with room to continue scaling.
Mainstream users benefit from these higher speeds, while overclockers and enthusiasts
that have been bumping their heads against the limits of DDR3 now have an entirely new
frontier to play in.