- The RAM you use in your computer operates using Double Data Rate (DDR). DDR RAM means that two transfers happen per clock cycle. Newer types of RAM are updated versions of the same technology, hence why RAM modules carry the label DDR, DDR2, DDR3, and so on.
- While all RAM generations are exactly the same physical size and shape, they still aren’t compatible. You cannot use DDR3 RAM in a motherboard that only supports DDR2. Likewise, DDR3 doesn’t fit in a DDR4 slot. To stop any confusion, each RAM generation has a notch cut in the pins at different locations. That means you cannot accidentally mix your RAM modules up or damage your motherboard, even if you buy the wrong type.
DDR2 #
DDR2 is the oldest kind of RAM you’re likely to come across today. It has 240 pins (200 for SO-DIMM). DDR2 has been well and truly superseded, but you can still buy it in limited quantities to upgrade older machines. Otherwise, DDR2 is obsolete.
DDR3 #
- DDR3 was released way back in 2007. Although it was officially superseded by DDR4 in 2014, you will still find a lot of systems using the older RAM standard. Why? Because it wasn’t until 2016 (two years after DDR4 launched) that DDR4 capable systems really picked up steam. Furthermore, DDR3 RAM covers a huge range of CPU generations, stretching from Intel’s LGA1366 socket through to LGA1151, as well as AMD’s AM3/AM3+ and FM1/2/2+. (For Intel, that’s from the introduction of the Intel Core i7 line in 2008 through to 7th generation Kaby Lake!)
- DDR3 RAM has the same number of pins as DDR2. However, it runs a lower voltage and has higher timings (more on RAM timings in a moment), so isn’t compatible. Also, DDR3 SO-DIMMs have 204 pins versus DDR2’s 200 pins.
DDR4 #
- DDR4 hit the market in 2014, yet still hasn’t taken complete control of the RAM market. A prolonged period of exceptionally high RAM prices put a pause on many people upgrading. But as prices decrease, more people make the switch, especially as the latest AMD and Intel CPU generations all use DDR4 RAM exclusively. That means if you want to upgrade to a more powerful CPU, you need a new motherboard and new RAM, too.
- DDR4 drops the RAM voltage even further, from 1.5V to 1.2V, while increasing the number of pins to 288.
DDR5 #
- DDR5 is set to hit consumer markets in 2019. But given how long the proliferation of a new RAM generation usually takes, expect to hear more about it in 2020. RAM manufacturer, SK Hynix, expect DDR5 to make up 25% of the market in 2020, and 44% in 2021.
- DDR5 will continue with a 288-pin design, although the RAM voltage will drop to 1.1V. DDR5 RAM performance is expected to double the fastest standard of the previous DDR4 generation. For example, SK Hynix revealed the technical details of a DDR5-6400 RAM module, the fastest possible allowed under the DDR5 standard.
- But, as with any new computer hardware, expect an extremely high price at launch. Also, if you’re considering buying a new motherboard, don’t focus on DDR5. It isn’t available yet, and despite what SK Hynix says, it will take Intel and AMD a while to prepare
