The dawn of DDR5 RAM is near. But if you expect the memory standard to support your old DDR4 RAM modules, you’re out of luck.
The pin layout on a DDR5 RAM stick is slightly different compared to DDR4. At first glance, they look the same. But on closer examination, the “key notch” on the DDR5 module veers more to the left.
Hence, you shouldn’t be able to insert a DDR4 module into a DDR5 slot, and vice versa, unless you want to risk breaking something.
The standards body behind the DDR5 RAM spec, JEDEC, announced the pin layout would be slightly different on the new memory last year. But now we have a DDR5 RAM module from Kingston in our hands, and can confirm it’s true.
This week, the memory maker ADATA also published a picture to underscore the slight difference in the pin layout. “DDR5 U-DIMM modules have the same dimensions and pin count as DDR4 modules. (But) The most obvious difference is the position of the fool-proof notch,” it said.
It’s also no surprise, if you follow RAM standards. Over the years, the PC industry has continually changed the position of the key notch. The big question is whether motherboard makers will go out of their way to support both DDR5 and DDR4 RAM on the same board once Intel’s Alder Lake CPUs launch later this year. The processor family will be the first to support DDR5 RAM, with AMD's silicon slated to join the party next year with the Zen 4 launch.
It’s a good bet motherboard makers will largely only support one RAM class on their products to save on costs and space. A recent leak from Asus signals the company’s motherboards for Alder Lake will be clearly marked to support DDR5 or DDR4. So if you plan on buying Intel's next-generation chips, you'll likely have to adopt one RAM spec over the other. The bad news is that DDR5 RAM may cost significantly more than DDR4.