DDR5 is excepted to be twice as fast as DDR4, initially DDR5 was expected to run at 4800MHz which is actually double the standard speed of DDR4 which is 2400MHz. But of course most people are running their systems at around 3000MHz or more meaning the stock improvements of the newer memory isn’t as impressive. That is why the major manufacturer of DRAM, SK Hynix decided to ‘kick it up a notch’ and decided to roll out kits that can go up to 8400MHz.
Although, realistically consumers who are willing to snag a some of this faster memory for their own setup should get used to seeing speeds around the 4800-6400MHz range, with the faster 8400MHz targeted at mostly the server market. But regardless, DDR5’s memory can be accessed while it memory banks are being refreshed leading to lower latency.
Counterintuitivly higher speeds would mean lower power consumption because of the lower transistor size. The average DDR4 memory take up about 1.2V while the newer DDR5 would take only 1.1V, this wouldnt seem much in a desktop setup but in mobile device like a notebook computer this would mean faster memory with better battery life.
Another advantage of smaller transistors is the greater storage density i.e., the amount of Gigabytes each module can hold, this is excepted to roughly double, so expect to more 16GB kits out in the market. Now these DDR5 kits wont be available to the average consumer for a while even though they are already introduced into the market, although there have been some variants of DDR5 incorporated into high end smart phones, buying a couple of sticks of RAM for your personal PC might not be possible at this moment, not to mention there aren’t any consumer platforms that can support DDR5, even the next generation of both AMD and Intel CPUs due to come out later this year are still going to be based around DDR4.
So if you are waiting to upgrade you PCs don’t wait around for DDR5 platform to come around, it been estimated that consumer DDR5 may start to showup in consumer PC’s and servers till late 2021 and might represent less than half of the DRAM market by the mid 2022.