As new CPU and GPU architectures mix the market pretty much every year—sometimes more than once a year. Yet in spite of the influence that system memory can have on a PC’s performance, the industry has relied on the same basic memory architecture for what seems like an perpetuity—in tech time, at least.
DDR3 SDRAM (the third generation of double data rate synchronous DRAM) was introduced way back seven years ago. Now the PC industry is finally making to transition to DDR4 memory.
Why has it taken so long to come to market?
Part of the reason for the long gestation period is that memory manufacturers compete more on price than performance. And unlike the CPU and GPU markets, where just two companies dominate the market, memory standards are developed by a committee: The Joint Electron Devices Engineering Council (JEDEC). If you want a standard to develop slowly, do it by committee (consider how long the IEEE is taking to ratify the 802.11ac Wi-Fi standard).
DDR4’s lower power requirements—and the consistent reduction in waste heat—will be this technology’s USP.
JEDEC, which consists of every memory maker in the world, started work on the DDR4 spec in 2005—two years before DDR3 even hit the market—but the first test samples didn’t appear until 2011. DDR4 memory finally hit the market last year in very incomplete supply.
So what exactly is DDR4 RAM?
There are a lot of deeply technical aspects to DDR4, but we won’t go into that much detail today. The two key improvements in DDR4 are power consumption and data transfer speed, thanks to the development of an all-new bus.
DDR4 memory
DDR4 memory will deliver important benefits in terms of performance and power consumption.
DDR3 generally requires 1.5 volts of electrical power to operate. DDR4 needs 20 percent less—just 1.2 volts. DDR4 also supports a new, deep power-down mode that will allow the host device to go into standby without needing to refresh its memory. Deep power-down mode is predictable to reduce standby power consumption by 40- to 50 percent.
Less power draw means less heat and longer battery life, so laptops and servers are expected to be the biggest beneficiaries of the jump to DDR4. Servers can be deployed with as much as a terabyte of memory and they routinely operate 24/7, so the power bills to keep them running—along with the onboard fans and outboard ventilation systems to keep them cool—can be enormous.
Mid-range and high-end laptops routinely ship with 8GB of memory, so the 20-percent decrease in power consumption is more significant for extending battery life than reducing utility bills. The LCD panel remains the biggest power draw, and the CPU eats its share of juice, but every little bit helps.
Smartphones and tablets will advantage from DDR4 memory, too. Because they typically come with only 1GB or 2GB of memory—and their displays consume much more power than their memory—they’ll benefit much like laptops will, from lengthy battery life rather than lower power bills.