DDR3 has reached the end of a long run, and DDR4 is the future
What Is the difference between DDR4 and DDR3? While DDR4 is the memory of option dDR3 had a good run. DDR3 was released in 2007 and used on everything from Intel’s LGA1366 via LGA1151 (6th/7th Gen Core only), combined with AMD’s AM3/AM3+ and FM1/2/2+. But all modern platforms (because 2017) have changed to being DDR4 only, and most Intel platforms changed from DDR3 together with the 6th Gen Skylake CPUs. So if you’re looking at an 8th or 9th Gen Core CPU or later, or an AMD Ryzen processor, you’ll need DDR4.
However, what about older CPUs, and is there so much difference between DDR4 and DDR3? The brief response is that yes, there are plenty of differences, but the majority of the time that your motherboard will make the decision for you. DDR3 can not be used by A motherboard with slots that are DDR4, also you can not put DDR4 to a DDR3 slot. But let us dig into the gaps.
DDR4 operates at a lower voltage than DDR3. DDR4 usually runs at 1.2 voltsdown from DDR3’s 1.5V. It doesn’t sound like much, and there are really low voltage DDR3L modules in addition to fan DDR4 modules at which voltages overlap, but the standard modules are 1.2V vs. 1.5V. The difference may account for a 15W savings over DDR3–maybe not a lot for a house user.
Another large gap between DDR3 and DDR4 is speed. DDR3 specifications formally start at 800 MT/s (or Millions of Transfers per second) and end at DDR3-2133. Some overclocking modules went as high as DDR3-3200 and much more, but those are speeds. DDR4 starts using support for up to DDR4-3200, at 1600 MHz –and overclocking kits can go as large as DDR4-4800. The speed means an rise in bandwidth.
This unfortunately comes with an increase in latency as well, while maintaining a general latency comparable to DDR2 and DDR3, but the increased clock rate makes for faster transfers. DDR3-1600 CL10 as an example has a latency of 12.5 nanoseconds to initiate a read. DDR4-2666 CL17 has a latency of 12.75 nanoseconds–essentially the same. However, the DDR4 supplies 21.3GB/s of bandwidth compared to 12.8GB/s to get DDR3.
How does this translate to performance? Since Anandtech found in certain detailed benchmarks comparing DDR3 and DDR4, neither has been a clear performance leader. The gap between DDR4-2133 and DDR3-2133 was negligible in a number of applications, which range from Handbrake video conversion. DDR3 was slightly faster about half of the time, and only a couple of percentage points separated both memory types.
There are other differences. Many will not work in desktop motherboards, although it is possible to get larger memory modules. 32GB is officially listed by the Core i7-4770K while that doubles to 64GB, as the highest supported RAM. Core doubles to 128GB, aided in large part from the availability of capacity DIMMs.
But ultimately, the question of DDR3 vs. DDR4 will return to a choice of CPU and motherboard. There are a few select instances where the two memory types are encouraged, but you end up with half as many slots (eg, two DDR3 and two DDR4, instead of four DDR4). And though DDR4 will cost a bit more than DDR3 (roughly $70 for 16GB DDR4-2666 compared to $60 for DDR3-1600), it’s the better choice for any new PC.