DDR4 vs DDR3: Little Comparison & What To Expect
DDR4 DRAM memory technology is set to replace DDR3 soon later this year, but what is DDR4 exactly, and what are the advantages of such technology compared to the DDR3? Well then, let’s take a brief look at DDR4, along the advantages that it promises to the table, with the help of a nice infographic from our friends at Crucial Memory.
EFFICIENT, FASTER, & HIGHER CAPACITY MODULES:
Compared to DDR3, the DDR4 technology features a lower power consumption @ 1.2v in order to operate at its standard frequency. Low voltage standards are around 1.05v, which is great for mobile devices. Capacity is a huge leap too at 16GB/stick, compared to DDR3′s 8GB/stick, thanks to DDR4′s higher density modules. Speed is rated at 2133Mhz, and is effectively twice as fast compared to the DDR3′s 1000Mhz standards. Theoretically, DDR4 is going to be much faster compared to DDR3, but will introduce higher latency compared to DDR3.
The future of memory technology with DDR4 is looking great, but there are caveats. You see, DDR3 uses Multi-Drop BUS topology, while the next-gen DDR4 will utilize Point-to-Point topology. In layman’s term, DDR4 will only operate at Single Channel with 1 stick, Dual Channel with 2 sticks, and will only operate at Quad Channel with 4 sticks respectively. That said, you’re left with little headroom for upgrade, as you’re bound with a maximum of 32GB for Dual Channel configuration for example.
|Voltage (core and I/O)||1.5V||1.2V||Reduces memory power demand|
|VREF inputs||2 – DQs and CMD/ADDR||1 – CMD/ADDR||VREFDQ now internal|
|Low voltage standard||Yes
(DDR3L at 1.35V)
|Memory power reductions|
|Data rate (Mb/s)||800, 1066, 1333, 1600, 1866, 2133||1600, 1866, 2133, 2400, 2667, 3200||Migration to higher‐speed I/O|
|Densities||512Mb–8Gb||2Gb–16Gb||Better enablement for large-capacity memory subsystems|
|Internal banks||8||16||More banks|
|Bank groups (BG)||0||4||Faster burst accesses|
|tCK – DLL enabled||300 MHz to 800 MHz||667 MHz to 1.6 GHz||Higher data rates|
|tCK – DLL disabled||10 MHz to 125 MHz (optional)||Undefined to 125 MHz||DLL-off now fully supported|
|Read latency||AL + CL||AL + CL||Expanded values|
|Write latency||AL + CWL||AL + CWL||Expanded values|
|DQ driver (ALT)||40Ω||48Ω||Optimized for PtP (point-to-point) applications|
|DQ bus||SSTL15||POD12||Mitigate I/O noise and power|
|RTT values (in Ω)||120, 60, 40, 30, 20||240, 120, 80, 60, 48, 40, 34||Support higher data rates|
|RTT not allowed||READ bursts||Disables during READ bursts||Ease-of-use|
|ODT modes||Nominal, dynamic||Nominal, dynamic, park||Additional control mode; supports OTF value change|
|ODT control||ODT signaling required||ODT signaling not required||Ease of ODT control, allows non-ODT routing on PtP applications|
|Multipurpose register (MPR)||Four registers – 1 defined, 3 RFU||Four registers – 3 defined, 1 RFU||Provides additional specialty readout|
In addition, no current motherboard and CPU in the market supports DDR4. Meaning you have to buy a new motherboard, and CPU to take advantage of the said technology which will be probably available upon the release of the next-gen chipsets and micro-processors. Reports suggests that Intel’s upcoming Enthusiasts grade Haswell-E chips will support DDR4, while AMD will support it probably in the late 2014 based on JEDEC’s roadmap. Like any other technological advancements, expect the initial cost of DDR4 to hurt your wallet.
Intel and several memory manufacturers showcased the DDR4 technology at the recently concluded Intel Developer Forum, and event suggests that DDR4 will see its first real world action with servers, rather than with consumer grade hardwares with the exception of the soon to be released Haswell-E which is based on Intel’s server grade chips.
AWESOME SAUCE: Crucial / Micron